There has been continuing interest in the case study known widely as the "German super baby." I did a brief post in November linking to the New Scientist article based on the original journal paper (Schuelke, et al., 2004. Myostatin Mutation Associated with Gross Muscle Hypertrophy in a Child. New England Journal of Medicine 350:2682-8), but did not read the original paper and related literature at the time.

As the New Scientist article summarizes, a single point mutation in the gene coding for the protein myostatin causes the condition, which appears to be partial in the boy's mother, who has one mutated allele for the gene, and more dramatic in the case of the boy, with both alleles mutated. Myostatin's function is to inhibit muscle development, and the mutation produces a non-functioning version of the protein. Thus, muscle development continues without inhibition.

Why do we have a protein to inhibit muscle development? Because it is just as important in development to turn processes off as it is to turn them on. If a system in the body is out of proportion to the rest of the body systems, there can be trouble. There always looms the possibility of future health problems, when one's body is out of whack. For example, I found this comment (authenticity unconfirmed, but compelling nonetheless) by "Kangarooistan Man" on a page discussing the condition:

...my father and I both have the "superbaby" mutation. severe myostatin deficiency. My father's bones are near unbreakable and he became locally famous after lifting a minivan.
His strength is comparable to between 3 and 5 normal men and his strength peaked at about the age of 40. His brother Joseph is suspected of having the mutation as well.
Our muscles grow at incredible rates, but don't grow much larger. The muscle fibre packs tightly- so tightly in fact that they tear under their own strength, causing us to suddenly collapse for no apparrent reason with massive muscle tears.
We have body fat of >1% and abnormal muscle definition.
...my father once jokingly held a washing machine in his outstretched arm, obviously considerably more than this 10 lb from the 4 yr old.

I don't know what we are really capable of, but I can tell you from experience that myostatin deficiency is not always a benefit. The constant pain from muscle growth and the inevitable tears that follow are horrendous and it is suspected that the huge muscle mass presses on our blood vessels, forcing blood pressure up and making our hearts less effective.

I'm sure warnings like this will not prevent the next generation of athletes from using whatever "myostatin inhibitor" someone will eventually manage to produce and put on the black market.

Of course, there could be legitimate uses in humans for such a drug, and an obvious discussion has ensued for potential treatment of conditions such as muscular dystrophy. As some researchers in the New Scientist article point out, however, the problems associated with MD are more complicated than just weak muscles, so myostatin inhibition as a treatment is likely still many years away. But, there has been some success in trials using mice with a condition analagous to muscular dystrophy in humans (Benabdallah, B. F., Bouchentouf, M. and Tremblay, J. P., 2005. Improved success of myoblast transplantation in mdx mice by blocking the myostatin signal. Transplantation 79:1696-1702).

What was most intriguing to me about the results of my journal search on "myostatin mutation" was that most papers involve research on livestock. There are breeds of cows with "double muscling" that have this mutation, which is attractive to beef producers. It was in this context that several mutations in the myostatin gene were originally identified in 1997 (McPherron, A. C. and Lee, S. J., 1997. Double muscling in cattle due to mutations in the myostatin gene. Proceedings of the National Academy of Sciences of the United States of America, 94:12457-12461). The discussion involves how the information might be used to manipulate the genetics of other farm animals similarly. The idea that myostatin's function is specifically as muscle growth inhibitor was apparently not introduced until 2002 (Kocamis, H. and Killefer, J., 2002. Myostatin expression and possible functions in animal muscle growth. Domestic Animal Endocrinology 23:447-454). Texel sheep, a "meaty" breed, apparently have a similar mutation as that identified in the human case, a single point mutation of G to A in a myostatin allele (Clop et al., 2006. A mutation creating a potential illegitimate microRNA target site in the myostatin gene affects muscularity in sheep. Nature Genetics 38:813-818).

As far as I can tell, that sums up the majority of what is known about myostatin. I predict that in a decade or so we will be hearing about a big MI (myostatin inhibitor) ring being broken up, as high school and college kids feel pressure to use it in order to compete, but start collapsing due to muscle tears and circulatory problems. Until the societal and material rewards of a stellar education surpass those of stellar athleticism, the performance enhancement arms race will continue... but that is for another rant, at another time.

Addendum: Apparently there are already a lot of supplements marketed to athletes as "myostatin inhibitors." It is clear from the literature, however, that such a drug has yet to be developed. Fortunately, some sites are honest enough to steer people away from the latest patent medicine.

Here are some pictures, real or not, purporting to show myostatin-deficient animals and humans.

Labels: genetics, humans

Almost as a reiteration to my earlier post, here is another article close on the heels of the last, about drying conditions in the West. Climate change is not a vague, unproven myth that wacko lefties perpetuate in order to undermine Big Business. It's here, folks, and because it is being combined with other fast-acting anthropogenic effects (that I previously discussed), ways of life and species assemblages in the West will be radically changing in the next couple of decades.

And, having done ecological research (my dissertation) in high altitude zones of the "sky islands" myself, on species that may cease to exist in the southern half of Arizona within my lifetime, it is not exactly with glee that I draw your attention.

Labels: biodiversity, ecology, environment, evolution, invasive species

Frans de Waal is my new hero. He has performed a body of research on various non-human primates which has demonstrated that at least a minimal level, morality is a byproduct of sociality, rather than a unique human construct. His experiments are well designed, and essentially make it clear that the "golden rule" morality of "do unto others as you would have them do unto you" is an important system that helps hold many primate groups together.

As he writes in an essay from the New Scientist ("The animal roots of human morality," October 14, 2006, pp. 60-61):

In The Descent of Man [Darwin] wrote: "Any animal whatever, endowed with well-marked social instincts... would inevitably acquire a moral sense or conscience, as soon as its intellectual powers had become as well developed, or nearly as well developed, as in man."

It is not hard to recognise the two pillars of human morality in the behaviour of other animals. These pillars are elegantly summed up in the golden rule that transcends the world's cultures and religions: "Do unto others as you would have them do unto you." This unites empathy (attention to another's feelings) with reciprocity (if others follow the same rule, you too will be treated well). Human morality as we know it is unthinkable without empathy and reciprocity.

It has always been strange and interesting to me (as de Waal makes it clear it is interesting to him as well) that this basic rule does not seem to be recognized by a lot of people as the cornerstone to human morality. I believe it is embraced by secular humanists, but in many cultures, religion has interfered with and been confused with human morality, when in fact morality predates religion and in fact has nothing to do with religion. Religious morality is actually a set of rules to distinguish the practitioners of certain religions from the rest of the world, the "outsiders:"

Our evolutionary background makes it hard to identify with outsiders. We've been designed to hate our enemies, to ignore people we barely know, and to distrust anybody who doesn't look like us. Even if we are largely cooperative within our communities, we become almost a different animal in our treatment of strangers.

Also:
Empathy is the one weapon in the human repertoire able to rid us of the curse of xenophobia. It is fragile, though. In our close relatives it is switched on by events within their community, such as a youngster in distress, but it is just as easily switched off with regards to outsiders...
(de Waal, "The empathic ape," New Scientist October 8, 2005 p. 52)

This relates to a previous post of mine on the tendency for humans to "switch off" their empathy when communicating over the internet, either to a specific individual through email, or via the blogging culture of mass demonization of a defined group or individuals supposedly representing that group.

It also turns out that the effort to conform in order to fit into society is not limited to humans, either. In a Nature article (Andrew Whiten, Victoria Horner & Frans B. M. de Waal, 2005. Conformity to cultural norms of tool use in chimpanzees.
Nature 437:737-740), de Waal and colleagues found that when two chimpanzees, from two different social groups, were each taught a different way of working the same machine to receive food, chimps not only learned the method taught the chimp from their group, but preferred it even when they figured out the other way too. From the abstract:

... A subset of chimpanzees that discovered the alternative method nevertheless went on to match the predominant approach of their companions, showing a conformity bias that is regarded as a hallmark of human culture.

The conclusion of that article states their experimental results plainly:

...[W]e found evidence of a conformist bias, identified in numerous human studies as a powerful tendency to discount personal experience in favour of adopting perceived community norms...

These results suggest an ancient origin for the conformist cultural propensities so evident in humans.

Here's one more interesting paper, which found that primates participating in games designed to see if animals will always act in their self-interest, often did not. This is a well known idea about humans in economic circles. For example, there is a game in which two people have to agree to accept a certain amount of money. If one person does not agree, neither gets the money, but if they both agree, they both do. If two people are given the same amount of money, each happily takes the reward. But although it is always to a person's benefit to accept any amount of money, most people will reject the money if they find out that the other person would get significantly more than they do. This result probably is not too surprising to most of us.

It is interesting, though, that de Waal and his colleagues have found a quite similar behavior in primates (Sarah F. Brosnana,and Frans B. M. de Waal, 2005. Across-species perspective on the selfishness axiom. BEHAVIORAL AND BRAIN SCIENCES 28:818):

We know that some nonhuman primates react to being relatively underbenefitted compared to a conspecific, which is irrational according to a strict self-interest paradigm.

I find myself disagreeing with the statement that this behavior is irrational, however. In the context of sociality, it is not, necessarily. The basis of sociality is reciprocity, and therefore it makes sense that even animals behave as if there has been an injustice in this case. I think a functional society needs to demonstrate that there is a minimum of justice. Those human societies in which this minimum is not met are not productive, or functional, in my opinion.


And based on experiments to look at the idea of sharing, another social behavior, in primates, these same authors state:

...there was virtually no sharing between the privileged individual and their less well-endowed partner...It is interesting, therefore, that the relatively benefited individuals did not exert more effort to equalize rewards.

Interesting, perhaps... but certainly consistent with human behavior as well.


Based on this extensive research on non-human primates, the origins of both conformity and morality are clearly pre-human. Each is a double-edged sword - the dangers of groupthink (especially within a "social group" of leadership) should be clear to everyone, and the "golden rule" can create problems when people across cultures (an everyday occurrence in today's world) are attempting to interact - treating someone the way you would want to be treated results in people taking offense all the time.

Humans love to believe we transcend biology, because we are not mere "animals." Based on de Waal's work, however, it seems we may be doomed to be limited by the structure of brains adapted to functioning within small societies. Globalization has been far too rapid to even imagine that any evolution to cope with its intricacies has occurred.

Labels: brain, empathy, evolution, morality, sociality

I thought about doing a post on all the wasp mimics out there, but within the flies (Diptera) there are plenty, and it clearly evolved multiple times - in most cases, not all the species within the following family are mimics. Obviously it would be some benefit for any insect to be thought a wasp by a vertebrate predator. Flies cannot sting for defense, so some of them just look a lot like wasps so predators will think they can sting. The ways in which they mimic wasps are fascinating.

The following families include wasp mimics: Micropezidae, Conopidae, Mydidae and Syrphidae. I'm surely missing some - don't be shy about pointing it out, all you Dipterists out there.

There is a whole family of bee mimics as well, the Bombylidae (the bumblebee genus is Bombus). They are big fuzzy things (below right), but if you look closely, you will see only two wings, which gives away their lineage - all bees and wasps (and all orders of insects except for the flies) have four wings.

But I'm more interested in the wasp mimics here. I'll start with my favorite, a Micropezid I caught in Costa Rica, at the La Selva research station. These are fantastic mimics, and a still photo just doesn't do them justice because their behavior is an important part of the package. You can see the fly has a pointy abdomen, which helps, and when grabbed, it pokes its abdomen into the grabber's skin repeatedly as if to sting. (Kinda cute, since it's completely harmless.) The other important combination of morphology and behavior has to do with the long forelegs, which end in white tips (which you should be able to see in the photo, along the edge of my thumbnail). In the tropics especially, the long antennae of stinging wasps have white or yellow tips. Flies, as a group, have very small antennae, but this family of flies has long legs. It was a quicker evolutionary step for the mimic species to use its forelegs to mimic antennae, than to develop long antennae itself. So you will see this fly walking rapidly along leaves in the manner of wasps, tapping its forelegs in front of it just as wasps use their antennae. It's really amazing to watch. (Although this fly family is more ubiquitous in the tropics, there are North American species and I have seen them in central Virginia.)

Conopids have a generally different look, mimicking thread-waisted wasps (Sphecidae) rather specifically. A common wasp-mimic morphology is to have a somewhat constricted abdomen, because a distinguishing character of the Hymenoptera (ants, bees, wasps) is a distinct constriction in the first few abdomenal segments, which means that hymenopterans are more or less restricted to liquefied foods, but also allows flexible reach for the abdomen when stinging prey or for defense. The conopids combine this with the elongated abdomen characteristic of sphecid (digger) wasps. I'm not aware of any specific behaviors that help promote their ruse.

Some Mydidae (mydas flies) apparently go for the pompilid (spider wasp) look. According to the source for this photo of Mydas clavatus, Tom Murray, it is mimicking spider wasps in a particular genus, Anoplius. Pompilids have a quite characteristic look of a black body and darkly pigmented wings. The photo on the right is Anoplius.

The syrphids (hoverflies) are not so precise in their mimicry. Here are two, with one clearly mimicking a bumble bee, and the other just looking generally wasp-like with its black and yellow markings. Their behavior does not necessarily contribute to the show; as their common name suggests, syrphids spend a lot of time hovering, which is generally unwasplike.








Thus mimicry takes many forms. It is interesting that some mimics seem to be modeling specific insects while others just seem to have the general look of wasps or bees. Does the selection pressure differ for these mimics, and why? Perhaps the generalist mimics live where there are a big enough variety of stinging Hymenoptera that they don't need to get specific. Why do some converge on specific families? Is there a dominant model present in those habitats? I'll admit up front that I have not done a literature search, so I don't know what is known specifically about the evolution of mimicry in these groups. I just like them because they are so cool.

The only picture of mine above is the worst one by far, of the micropezid. The syrphids and Anoplius come from Forestry Images, a wonderful image database, and the rest are by Tom Murray, and used with his permission. See many wonderful fly images of his here.

Labels: bees, biodiversity, cool bugs, ecology, evolution, flies, insects, wasps

An observation that has been sitting on my back burner for awhile is the apparent phenomenon that mothers tend to be more responsive to their babies' cries than fathers. I don't mean this in the sense of a behavioral response, but rather, as a physiological response. For example, I'm amazed at how loud our daughter has to cry at night to wake my husband up - sometimes I hear it through ear plugs before he seems to notice.

Of course, this is a single observation. Ever the scientist, I formed two possible hypotheses about this phenomenon, which, based on conversations with other couples with small children, seems to be fairly widespread. One hypothesis is that it is usually the mother who has the heightened response, and that it could be a hormonal issue. (It probably is partly associated with breast feeding, but I stopped nearly a year ago and still have the response.) Another hypothesis is that it is the primary caretaker who has the heightened response, and just seems like moms because, surprise, they are usually the primary caretakers.

My bit of unscientifically collected data supporting the first hypothesis rather than the second is that out of probably half a dozen couples, it is the mothers who have the response, even though in two of these cases the father has been the primary caretaker. So I'm guessing there is some real physiological basis in this.

Real scientific studies could tell me whether I'm right or not. Surprisingly, though, an hour plus of searches both on Web of Science and Google produced nothing concrete on this topic. The studies I did find were nearly always on mothers only (which I found annoying), and mostly compared mothers and non-mothers, or especially, mothers of "collicky" vs non-collicky babies. A few studies, below, were a bit more interesting to me.

First:

Purhonen M, Kilpelainen-Lees R, Paakkonen A, Ypparila H, Lehtonen J, Karhu J, 2001. Effects of maternity on auditory event-related potentials to human sound.
NEUROREPORT 12 (13): 2975-2979 SEP 17 2001

Abstract: Auditory event-related brain potentials (ERPs) were recorded in response to an emotional (a baby's cry) and a neutral (a word) stimulus in a group of mothers 2-5 days after childbirth (n = 20) and in control women (n = 18) who were not in the state of early motherhood. For each mother, her own infant's cry was recorded and used as the cry stimulus, whereas a strange baby's cry was used for control women. The word stimulus was identical for both groups. Stimuli were presented in intermittent trains in order to study the arousal responses to the first stimuli of the trains, and refractoriness of ERPs during stimulus repetition. The N100 responses were significantly larger in amplitude in mothers than in control women, not only to the emotional cry stimuli but also to the neutral word stimuli. The finding suggests a general increase in alertness and arousal in mothers, which may be necessary in enabling the mother to be continuously alert to her infant's needs. This allows good care of the infant and may be essential in building an emotional tie between the mother and her child.

I think this study also needed an additional test group of mothers responding to cries of strange children. The conclusion (about the "emotional tie between the mother and her child") may not quite be supported if any baby's cry elicits the same response. Or perhaps it is, given that mothers are going to be exposed to their own baby's cries more often. Because we are a social species, though, that would be relevant and interesting information.

It's not surprising mothers and non-mothers differ on this of course, but what about fathers? I really think this is an obvious thing to test. Aren't "emotional ties" with dad important? (I checked these authors and there was not a paternal follow-up to this paper.)

Here's another dealing with mothers' brains - it appears to be an unpublished pilot study that I found online. It suggests that the cingulate region of the brain (part of the limbic system, which is associated with emotional respons) is involved with maternal response to cries. Wish they had done it with fathers too!

Feasibility Of Using fMRI To Study Mothers Responding To Infant Cries.
J.P. Lorberbaum, J.D. Newman, J.R. Dubno, A.R. Horwitz, Z. Nahas, C. Teneback, M.R. Johnson, R.B. Lydiard, J.C. Ballenger, M.S. George.

This small pilot experiment demonstrates the feasibility of studying maternal response to infant cries in a fMRI scanner environment. It tentatively supports the notion that the cingulate is involved in response to infant crying. Consistent with some monkey lesion work, it suggests that the ROF may also be involved (2). In designing follow-up studies, we are considering such factors as maternal and infant temperament, the type of infant cry, using each mother's infant's own cries, the appropriateness of our control stimulus, postpartum timing, and allowing a mother to actively terminate the cries as in natural settings. Future work in this area may lead to understanding the brain basis of mother-infant interaction and the biological roots of child neglect and abuse.

Here's one that looks at fathers vs. nonfathers:

Fleming AS, Corter C, Stallings J, Steiner M, 2002. Testosterone and prolactin are associated with emotional responses to infant cries in new fathers.
HORMONES AND BEHAVIOR 42 (4): 399-413 DEC 2002

Abstract: To determine the responsiveness of new fathers and non-fathers toward infant cues, we exposed fathers and non-fathers to infant cries and to control stimuli and we measured affective, heart-rate, and endocrine responses, including salivary testosterone and cortisol and plasma prolactin concentrations prior to and after cry presentations. We found that (1) fathers hearing the cry stimuli felt more sympathetic and more alert compared to groups who did not hear the cries or to non-fathers who heard the cries; (2) fathers and non-fathers with lower testosterone levels had higher sympathy and/or need to respond to the infant cries than fathers with higher testosterone levels; (3) fathers with higher, as opposed to lower, prolactin levels were also more alert and more positive in response to the cries; (4) fathers hearing the cry stimuli showed greater percentage increase in testosterone than fathers not hearing the cry stimuli; (5) experienced fathers hearing the cries showed a greater percentage increase in prolactin levels compared to first-time fathers or to any group of fathers hearing control stimuli; finally, (6) partial correlations with parity and experience entered as a covariates indicated that both experience and testosterone contributed to the variance in fathers' affective responses to infant cries. Taken together, these results indicate that, as with a number of other biparental species, human fathers are more responsive to infant cues than are non-fathers and fathers' responses to infant cues are related to both hormones and to caregiving experience.

While the previous papers looked at brain response, this one studied hormones, which makes it interesting, as it is not necessarily intuitive that fatherhood affects hormones. But, not only do having less testosterone and more prolactin make a father more responsive, but the cries themselves affected hormone levels, indicating a true physiological response to the sound of a baby crying. While one might expect maternal hormones to do this, it is more interesting to find it in fathers too.

From looking at this paper and the following...:

Storey, A. E., Walsh, C. J., Quinton, R. L., and Wynne-Edwards, K.E.(2000). Hormonal correlates of paternal responsiveness in new and expectant fathers. Evol. Hum. Behav. 21,79-95.

...it becomes obvious that the situation is not clear-cut; men who naturally have more testosterone are less responsive to their babies crying. It is not too hard to imagine couples out there where the father is the one leaping out of bed at the slightest peep.

Finally, I found a report (pdf) available here, which aims partly to look at brain responses to baby cries of both men and women, with and without children - exactly what I was looking for. Sadly, it is only a progress report from 2001, and my searches on the authors names came up empty on any follow-up. But again, the cingulate gyrus is implicated.

Here are the questions I would like to see addressed:

What effects do breast feeding or not have on physiological response to baby cries? Looking at hormones would be confounded by the hormones associated with the breast feeding, but an fMRI might be interesting.

What is the effect, if any, of actually having given birth to the baby, vs. adoption? (I suspect there has probably been some research on this aspect, but I haven't taken the time to delve into it.)

And of course, I would like to see the fMRI data for the test groups mentioned in the progress report above.

To close, here is my list of all the things that often sound, to me, like a baby crying (and my husband thinks I'm nuts, of course):

Dogs barking, cats meowing, trucks and cars going by on the freeway, train whistles, sirens, wind, kids playing outside, various large appliances, lawn mowers, snow blowers, leaf blowers, and the flywheel on my rowing machine.

That's all I could think of off the top of my head. I will edit the list as I think of more things. Please comment if you can add to the list or have any data to back up or refute my groundless assertions!

Labels: brain, gender, humans

The western U.S. has been under "drought" conditions on and off for the last ten years or so. Why is "drought" in quotes? Because drought is a relative condition, referring to less rain than normal - a level of rain considered drought in the Alaka`i Swamp would cause major flooding in Tucson.

So what is really going on in the West? The quick answer is that we probably don't have enough data really to know. Ten years of dry conditions is a blink in the long term. The ultimate question is if the current drier trend is something that will continue in the long term, or is really just a blip, and the truth is that no one can know for sure.

But what we can know about is the long term climate of the past. A panel of scientists analyzing conditions in the southwest noted the following (from a NY Times article [sub. req'd]):

...the water allocation agreement for the basin, the Colorado River Compact, was negotiated in 1922 based on river flow records dating to the 1890s, when gauging stations were established. The agreement assumed that the annual river flow was 16.4 million acre feet -- enough to cover 16.4 million acres to a depth of one foot.

But for some time, the panel said, researchers have known that the early 20th century was unusually wet and that 15 million acre feet was a more accurate estimate of the flow. Recent studies based on tree rings put the figure lower still -- as low as 13 million acre feet -- and suggest that "drought episodes are a recurrent and integral feature of the region's climate."

The harsh reality is apparently that over the last couple of centuries at least, the typical amount of water in the west jibes pretty closely with conditions we are seeing more recently, and the period when the west became heavily settled coincides with an unusual wet spell, combined with technology (dams, etc.) that allowed people to use more of the water that is there.

The long term implications for this trend are far-reaching. Biologically, the landscape of the west has been irreparably altered by the introduction of dams and cattle. Both of these in turn have facilitated establishment by lots of invasive weeds that are massively altering the landscape further. Two examples: Salt cedar and Russian olive have taken over many riparian areas in the southwest, and are spreading north (probably helped by human-enhanced climate change). Salt cedar not only crowds out native plants and lowers the water table, but its excretion of salt changes the chemistry of the soil, making restoration of these areas especially difficult. Native riparian trees such as willows can compete with salt cedar under the natural cycle of floods, but thousands of dams (built to provide water and power to an increasingly unsustainable western human population) have disrupted this cycle, under which conditions salt cedar easily takes over, disrupting the entire ecology of the system, because so many animals, vertebrate and invertebrate, depend on the native willows.

Cheatgrass is an invasive grass that produces intense fires that occur much more often than the normal fire cycle to which the animals and plants of the Great Basin are adapted. Neither are cows, so in addition to drought itself, cheatgrass has gotten a lot of attention because it impacts "traditional" ranching in the area.

But the effects of the West suddenly finding itself quite overpopulated given the amount of water we can expect in the near future reach into the sociological as well. As one example of many, our local Women's Resource Center, which provides support primarily to victims of domestic violence, has to gear itself up every summer for a big run on its services; the drier the summer, the more domestic abuse, presumably because of family stress about financial problems.

The bottom line is that at the very least, the level and methods of ranching and agriculture that people have become accustomed to over the last few generations in areas defined as desert, based on their low rainfall, is no longer sustainable. There are different ways of ranching cattle that can significantly reduce problems associated with overgrazing, but people are slow to change. If we are not actually experiencing a "drought," but rather emerging from a wet period, dark times are ahead for rural western economies, because the cities will be grabbing the resources to sustain millions of people living in the desert. Forget about the cows...which if you are an ecologist such as myself, would be a silver lining in all of this, if the native ecosystems that are left weren't going to disappear along with them.

Labels: biodiversity, ecology, environment, invasive species

I was just getting ready to order some more dark amber maple syrup from my favorite sugarhouse, Green's Sugarhouse in Poultney, Vermont, when this article (subscription req'd - why, I'm not sure...) about the recent poor sugaring seasons due to warm temperatures this winter grabbed my eye. Here's a snippet:

Warmer-than-usual winters are throwing things out of kilter, causing confusion among maple syrup producers, called sugar makers, and stoking fears for the survival of New England's maple forests.

''We can't rely on tradition like we used to,'' said Mr. Morse, 58, who once routinely began the sugaring season by inserting taps into trees around Town Meeting Day, the first Tuesday in March, and collecting sap to boil into syrup up until about six weeks later. The maple's biological clock is set by the timing of cold weather.

For at least 10 years some farmers have been starting sooner. But last year Mr. Morse tapped his trees in February and still missed out on so much sap that instead of producing his usual 1,000 gallons of syrup, he made only 700.

...Over the long haul, the industry in New England may face an even more profound challenge, the disappearance of sugar maples altogether as the climate zone they have evolved for moves across the Canadian border.

Are U.S. maple forests going to be a thing of the past in a couple of generations? Remember, in much of the northeast American chestnut was the dominant tree until early in the last century, when the introduction of the chestnut blight via imported Asian chestnut trees destroyed our native species within 50 years.

Such a dramatic and destructive consequence of humans' compulsion to move species around the world (many for frivolous purposes), one might imagine, should have sparked a reassessment of the risks of such practices. But industry interests, i.e. short-term economic gain, have remained more powerful than the long-term interests of ecosystem health, even when one of the continent's most prominent and visible species was impacted, to everyone's knowledge at the time. The nicks and cuts on our native habitats from thousands of alien species and housing developments scattered here and there are relatively less noticeable.

So it's likely a losing battle with industries, not to mention very lifestyles, that contribute to climate change, but have a much more indirect impact than a fungal disease jumping from an imported to a native species. Those who would rather not deal with the issue often take the attitude that change happens, and whether or not humans are causing the current changes is irrelevant, because there were plenty of pre-human climate change episodes in earth's past, plenty of mass extinctions we had nothing to do with. One real difference between those events and the current one, however, is not only the accelerated speed at which these changes are occurring - the dinosaurs actually took millions of years to die out, while the loss of the chestnut was relatively instantaneous - but that a species is here to witness it that understands the implications of what it is witnessing.

No one growing up today knows the difference between a life with chestnuts and a life without. A hundred years ago though, those who depended on chestnuts for a living had to go through the agony of watching their very lives disappear with the trees. So it will probably be for those running the sugarhouses, many of which have been in the same family for generations. One reason I would feel the loss of this agricultural industry is that it is nearly the only one left that can't be converted into a factory farm. The most high tech sugarhouses run tubing from the trees to their boilers. Green's still does it the old-fashioned way: everyone in the family works nearly round the clock for a few weeks hauling buckets from the forest on a yoke. (The demanding nature of this work became particularly clear to me when I witnessed an 80ish, humpbacked grandmother stoke the flames with a log six feet long and the width of a telephone pole.)

In another hundred years, no one in Vermont will feel an emotional loss for the sugaring industry, because they will never have known it. But one more piece of the landscape will be gone, one more thread will be pulled out of the fabric of our environment. If humans weren't around, would it happen? Possibly. Would it matter? That one is a question for the philosophers. I'd like to know what you think.

Labels: ecology, environment, invasive species

Pharyngula has already had an excellent post and subsequent discussion about last week's Times magazine article, "Darwin's God." Of course that's not going to keep me from my own pontification. I agree wholeheartedly with PZ on most points, but I hope to add to the discussion by commenting on what I thought were the more irritating quotes from the article.

The spandrels vs. adaptation dichotomy irritates me. An evolutionary spandrel may become adaptive in a context different from why it appeared. But the biggest problem with the whole article is the discussion of human evolutionary adaptation. Such discussions seem to be getting more and more popular, but are just a sign that our society today has swung way back to the "nature" explanations from the "nurture" explanations that were prevalent in previous decades. They are not any more valid today than they were a hundred years ago, but people actually have this idea that scientists have figured all this stuff out, just because we know how to sequence a gene now. Culture is completely intertwined with ecology for humans, and yet everyone wants to make ecological arguments for why we do things. It makes no sense. Culture is so plastic that anything said about evolutionary pressures hominids faced a million years ago is a made up just-so story. Evolutionary psychology is bogus, because it's just too easy to make up any story about humans' past that fits your pet theory.

Maybe cognitive effort was precisely the point. Maybe it took less mental work than Atran realized to hold belief in God in one's mind. Maybe, in fact, belief was the default position for the human mind, something that took no cognitive effort at all.

Although at first reading this seems an outrageous statement to a true atheist, I think on one level it has validity - I just argue with its assumptions about why some people apparently find it easier to believe in a god than not. The number one reason is culture: most of us have been brought up to believe in a god, so that does indeed become the default position for the majority out there who aren't that interested in thinking the idea through. For most, following the culture we are born into is not only simpler, but probably more adaptive as well (in terms of reproduction). But what that means is different for every place and time in human history.

Folkpsychology, as Atran and his colleagues see it, is essential to getting along in the contemporary world, just as it has been since prehistoric times. It allows us to anticipate the actions of others and to lead others to believe what we want them to believe; it is at the heart of everything from marriage to office politics to poker. People without this trait, like those with severe autism, are impaired, unable to imagine themselves in other people's heads.

This is an important point (touching on the importance of human sociality without spelling it out as such), and relates back to a previous post of mine.

They had learned that, in certain situations, people could be fooled -- but they had also learned that there is no fooling God.

The bottom line, according to byproduct theorists, is that children are born with a tendency to believe in omniscience, invisible minds, immaterial souls...

OK, this was commented on at Pharyngula, but I just have to add my agreement that this is one of the stupidest things anyone could say, and illustrates that the author of the article doesn't understand atheism at all. It also relates to something I have pointed out previously, that just because young children do something doesn't make it genetic. It's mind-boggling they could go from the previous statement about how important sociality is, to this statement which assumes babies live in some sort of vacuum and learn nothing about the society around them. And yet everyone knows and comments on the silly things toddlers do in imitation of adults and other kids. Belief in Santa Claus, the Easter bunny, and God is learned.

"Our psychological architecture makes us think in particular ways," says Bering, now at Queens University in Belfast, Northern Ireland. "In this study, it seems, the reason afterlife beliefs are so prevalent is that underlying them is our inability to simulate our nonexistence."

I like this analysis of why afterlife belief is so prevalent. For each of us, the universe only exists as filtered through our bodily senses. There is no objective reality. So we cannot imagine a reality that does not involve the use of our senses. Because it is impossible to imagine it, our brains hurt less to assume it doesn't exist.

...religion filled people with "a new zest which adds itself like a gift to life . . . an assurance of safety and a temper of peace and, in relation to others, a preponderance of loving affections."

It is just as easy to argue that the negative elements of religion would be destructive. Picking and choosing the "positive" aspects of religion is ridiculous, as Mark Twain pointed out in satirical essays about people who attribute all good to God, but do not blame God for all the horrible disasters in life (which in the life of the average person on this planet, arguably way outnumber the good things).

...helped them attract better mates because of their reputations for morality, obedience and sober living.

Even if you argue that these are all components of successful religions, this is bogus because in most people's cases, this is only the facade and not how they actually live their lives. Was it more genuine in the past? No way to know. But clearly for the major religions today, there are too many cheaters in the system to make membership in a religion a reliable signal for a good mate. There is a literature on ecological relationships that shows the mathematical level at which a mutualism breaks down because the number of cheaters makes it nonadaptive to trust your partner - this selects against the cheaters, presumably, and in many nonhuman mutualisms, a balance is achieved through selection. But when it comes to humans, culture is once again complicating the issue. It is nonadaptive for beaten women to return to their mates over and over again, but domestic violence is often sadly a cultural norm. To an abused woman, there are usually other perceived social repercussions in defying that norm, not to mention the perception that they would be worse off without the beater. So nonadaptive behaviors on the individual level persist in humans (various other addictions are another example), due to cultural reasons that cannot be ignored when one is making 'evolutionary' arguments.

"Religious and secular rituals can both promote cooperation," Sosis wrote in American Scientist in 2004. But religious rituals "generate greater belief and commitment" because they depend on belief rather than on proof. The rituals are "beyond the possibility of examination," he wrote, and a commitment to them is therefore emotional rather than logical -- a commitment that is, in Sosis's view, deeper and more long-lasting.

Unlike PZ, I think I agree with this. There is more to being in some thing perceived as a religion than being a Trekkie. Yes, people love to form clubs, and that is an outgrowth of our sociality. But religion works best for forming groups because:

1) Most people hate to think - any teacher or professor knows this - because it takes more energy than not thinking. Religions are convenient for nonthinkers because since they involve non-factual matters of faith, there is always someone telling you how to think, so it is easy to be a member.

2) Religion also combines the group-forming with the comfort of someone telling you that your crappy little life has some larger meaning. It also tells you that you will live forever, which appeals to everyone's fear of death (which is completely natural - heck, yeah, I fear death, so I try not to think about it!). You are also being told in most successful religions that personal responsibility is not important. Either whatever happens to you is the fault of infidels, or you will be forgiven as long as you confess, etc. Man, how appealing is that?

3) Religion is much better in fostering the us vs. them dichotomy that humans again tend to by virture of sociality. Like ants, we have a need to recognize "nestmate" from "nonnestmate," because we are competing for resources with the "nonnestmates." Civil War reenactors don't have any particular adversary that bonds them as a group (except maybe all the non-Civil War reenactors who think they're nuts). Costumes, behavior, etc. all are useful many societies to recognize whether or not someone believes in your god or the wrong one.


In sum, I completely agree with others who found the idea that it is difficult to "resist" religion completely bogus. I, like PZ and others, feel no such tendencies whatsoever. Again it is clear the author doesn't truly understand what atheism is. For me, it is not only being a 'non-believer.' Much more important, it is being competely comfortable with a universe in which there is no God and in which where we are today was arrived at solely by chance. My worldview is as natural to me as the worldview of some one who claims to be 'religious.' Don't you dare patronize me by saying that it isn't, because it's just as easy for me to think you are the misguided nut as vice versa. I prefer live and let live, which means: don't try to convert me, and don't make laws affecting me that are based on your religion.

What is the true difference between natural atheists and natural theists? In my view, it is the desire to think deeply about the world at all levels, without having to believe that in the end my life has to have some sort of meaning that ties neatly into the natural world. My thought is the emergent sum of a lot of complex (to me) chemical and electrical processes. Death is the end of those processes, period. I used to wonder why open atheists were in the minority. (No matter what the polls say, I am skeptical that there are as few atheists as people believe.) Now I understand that the 'deep thinkers' that identify themselves as theists just need that crutch; they need to think that their life somehow has meaning within the vast unknowable universe. This seems a natural state for a social species - the need to be accepted by society could easily be projected onto a god as well, once the species achieves awareness that there is a lot more out there beyond their patch of forest. After all, your own personal god will never desert you, will always forgive you, etc. Those of us who don't feel the need to be accepted by a god may have less of a need to be accepted by society as well (although we tend to find our own godless societies to be a part of). We probably have transcended biology at some level, because knowledge has set us free.

Labels: evolution, humans, religion, sociality

I met one of those anti-immunization parents today. I imagine they spend a lot of time reading sites like these, put up by the holistic "health care" types who probably amongst them don't have two degrees to rub together - let alone any sort of training in biology. Here is a description of the qualifications of the author of the above site:

I was once a victim of the never-ending flow of propaganda from the medical establishment (which I think of as the "disease" establishment because they focus on disease rather than on prevention and wellness) who wants to maintain a monopoly on the word "cure" and who wants us to believe that we have no control over our own health and that our only hope to get "well" is with drugs, surgery and radiation. Below is my account about how I achieved optimum health without drugs, surgery or radiation.

Right. If she can't have perfect health, it must be the fault of doctors. Oh and, by the way, even though she couldn't understand a scientific paper if it was spelled out in one-syllable words, she's going to assert all this stuff she has heard is true.

I couldn't agree more with taking charge of one's own health. But it's not the doctors who want control, it's the insurance companies. There is also a lot for us to learn about some diseases such as cancer - from what I have seen, most forms of chemotherapy are roughly as effective (and counter-productive) as bleeding someone with leeches. But that's just because we don't know enough yet of the different types of cancer that can all look the same, just because they occur in the breast, for example. It's clear from recent developments that some treatments work fantastically well - if your cancer is the right type. We have a way to go in getting people typed properly, but we're getting there.

The science behind the success of vaccines couldn't be more clear, however. While there are risks involved in any activity, medical or non (who knows what environmental toxins have leached into the granola that Ms. Holistic is eating?), it is the risk/benefit ratio that matters when making the best choices for our survival. While the risk/benefit ratio of having chemotherapy is not predictable for a specific individual, and thus easy to second-guess, the risk/benefit ratio for a vaccine is both predictable and extremely low.

The last time I ran across an Anti-Vaccinite I just had to laugh, because she told me she had put off shots for her baby because she felt "his immune system should develop naturally, without anyone telling what to do." I would have explained to her on the spot that something "telling" your immune system "what to do" is exactly how it develops in the first place, but fortunately by this time she had done her internet research and come to the conclusion that it was best to go ahead and get the kid his shots. I was glad to see that the kid may actually end up with half a brain.

But the person I met today just disgusted me, and made me want to go into House mode. When I pointed out that her kids were far more likely to suffer from preventable disease than vaccination side-effects, she didn't respond or look at me. I'm sure she's heard it all from her doctor anyway. But what she and other Anti-Vaccinites fail to understand is that she is nothing more than a parasite on society. Any parent living a hundred years ago would have jumped at the chance to drastically reduce their children's chances of developing a fatal disease, because many of these parents had watched their kids die. A-V parents get away with it now and act smug because of a simple public health phenomenon: if enough of the kids around her kids are vaccinated, then her kids have a low probability of coming down with the disease. Of course, many vaccines are imperfect and the ideal is not to be exposed in the first place - the probability of which drops for my kid when you Anti-Vaccinites are running amok. Hopefully, my kid will never pay the price for your stupidity. But it's much less likely that your kid won't.

Labels: health, humans, vaccines

What do you think this sound is? Continue reading for the answer...

Since it's been two weeks since my last "cool bug" post, I thought I had better change the name of the series... we'll see where it goes from here.

Today's subject is a fruit fly, Rhagoletis juglandis. This is not related to the fruit fly of genetics fame, Drosophila melanogaster, which is in a different family. Nearly all drosophilids only eat fruit once it is rotting; flies in the family Tephritidae, including the genus Rhagoletis, feed on ripe fruit and thus are known to entomologists as the "true" fruit flies.



I will admit up front that these flies are mainly of interest to me as larvae (at the left), because they serve as hosts for one of my favorite parasitic wasps, Diachasmimorpha juglandis, below. R. juglandis larvae feed on and live in the fruit of the Arizona walnut (Julglans major) (i.e., the husk surrounding the actual nut), and D. juglandis females parasitize them through the walnut fruit skin.


The fly larvae live in groups in the walnut husk, sometimes by the dozens. All the larvae in a fruit may or may not have the same parents, if there have been multiple ovipositions in the fruit.




In the picture to the right is a mating pair of R. juglandis adults on a plastic walnut model. Males and females mate multiply, with several individuals if given the opportunity.





There are territorial contests by the males on the ripe walnuts while they are still hanging in the tree. This behavior is known as "boxing." The males stand on their hind legs and bat their forelegs and wings together. (In the picture to the left, the wings are only a blur.) The idea is that the winners of these contests have access to more females, who will come to the walnut to mate and lay eggs. Some poor females are forced to mate as they extrude their ovipositors to dig a hole in the husk in which to lay eggs; the males will grab them from behind and mate with them before they have a chance to oviposit. Sometimes, though, males are so intent on fighting with each other that they don't seem to notice a third male that is mating with the female on the fruit while they are going after each other.


While males are duking it out, mated females also get the opportunity to finally oviposit without harassment (left). A female drills a hole in the husk with the tip of her ovipositor (which eventually shows signs of wear) and deposits several eggs in a cavity just beneath the surface of the husk. These grow and feed inside the husk until they are ready to pupate, when they exit the fruit and burrow into the soil. Sometimes there are so many larvae within the husk of a walnut that their feeding is audible. Click here to listen to the sounds of feeding fly larvae in a walnut.

Unfortunately for the larvae, the racket they make chowing down on the walnut is their undoing... as will be revealed in the next Cool Bug of the Fortnight!

Here are references for more information on Rhagoletis juglandis:

Papaj, D.R., 1994. OVIPOSITION SITE GUARDING BY MALE WALNUT FLIES AND ITS POSSIBLE CONSEQUENCES FOR MATING SUCCESS. BEHAVIORAL ECOLOGY AND SOCIOBIOLOGY 34 (3): 187-195.

Henneman, M.L. and Papaj, D.R., 1999. Role of host fruit color in the behavior of Rhagoletis juglandis (Diptera: Tephritidae). Entomologia Experimentalis et Applicata 93:247-256.

Nufio CR, Papaj DR, Alonso-Pimentel H, 2000. Host utilization by the walnut fly, Rhagoletis juglandis (Diptera : Tephritidae). ENVIRONMENTAL ENTOMOLOGY 29 (5): 994-1001.

Labels: biodiversity, cool bugs, ecology, evolution, flies, insects

One of the most species-rich families of plants in Hawai`i is the Rubiaceae, or coffee family. Several of these will be apparent as you walk along the boardwalk in the Alaka`i Swamp. While 22 species of the rubiaceous genus Hedyotis are listed in the Manual of the Flowering Plants of Hawai`i (Wagner et al. 1999, Bishop Museum, Honolulu), one species, Hedyotis terminalis (manono), has dozens of subspecies and varieties listed. The Manual says that this species "is probably the most polymorphic species among Haaiian flowering plants except perhaps Metrosideros polymorpha" [ohi`a, described in Part 1].

You can say that again. As I began my research project, I brought specimens of most of the plants to the botanists at the National Tropical Botanical Garden in Lawa`i for identification. After a few months I had learned the local species well enough, but in the process I believe I brought specimens of H. terminalis to one botanist at least four times. It got to be a bit embarrassing, but eventually I got a feel for the gestalt of this species.

Which brings me back to the end of Part 1, in which I suggested that the word 'species' itself may be inadequate to describe the current state of Hawaiian plants along the evolutionary continuum. The Manual admits there is no easy way to classify either H. terminalis or M. polymorpha into multiple species. Similar problems exist in some insect groups. Those doing DNA analysis of island endemics usually find similar genetic variation within a species to that between related species, which means it is nearly impossible to find genetic markers to distinguish species. Only by doing an analysis of multiple genes and seeing where an individual insect falls out on a plot of other known insects is it possible to identify it genetically. As I did with some plants, I had similar problems recognizing with certainty one moth species, Scotorythra rara, the most common one in the swamp. Once again, with the help from an expert in that genus, I understood the range of variation in that species enough to recognize it on site.

But given these difficulties, how do we know these moths or plants are all in the same species? Morphology is certainly useful, and in many insects, genitalia structure is key for separating species. But is it definitive? I'm not sure. For most Hawaiian insects, some major information is missing - their ecology and behavior. Entomologists in the islands work almost entirely with dead specimens, knowing little about how they live their lives. Among the hundreds of insects I reared and called S. rara, there were not only dozens of food plants, but multiple morphologies of the larvae (which are inchworms). When I first began rearing the insects, I assumed all these would be different species. And no one has a clue about their mating behavior, which is theoretically crucial to the actual definition of a species - if two individuals can interbreed and produce fertile offspring, they are usually (but not always, especially in plants!) considered the same species.

There is another genus of moths that positively exploded in its radiation in Hawai`i, called Hyposmocoma. There are over 300 described species of Hyposmocoma, and many in description limbo. I would not be surprised if there are actually over a thousand (as there are of a more studied fly genus in Hawai`i, Drosophila). Unfortunately, these are tiny moths, and even less is known about their life histories than about Scotorythra. An eminent entomologist I worked with on occasion at the British Museum of Natural History had tried to work on the taxonomy of the group, and had simply given up. Many specimens he studied with similar genitalia had different wing morphology, and vice versa. The larvae are case bearers, meaning they hang out in a little silken bag, and for some species the structure of the case seemed to be distinctive. But for most, it is apparently not.

Why are species so hard to separate in Hawai`i? Evolution is a continuous process, that has no endpoint. But because the Hawaiian Islands are so recent in geological time, and it is so rare for any living thing to arrive there on its own over vast expanses of ocean, I believe we are still witnessing the messy sorting out of niche-filling. The traits of different species drift and become more distinct from each other through several processes, including physical separation (via geological events, for example) and assortative mating (in which more similar individuals mate and reproduce). In Hawai`i, we have to ask, who knows what a species is? because we have not found a way to actually watch how individuals from all of these different groups interact with each other, and the environment. Speciation is not an instantaneous process, and in Hawai`i, along the boardwalk of the Alaka`i Swamp, we are watching it happen.

The plants and insects of the swamp are finding their way. Unfortunately, the evolutionary process can no longer stay on its natural course in Hawai`i, because of the habitat destruction and thousands of alien species that are invading the natural areas like the swamp and creating selection pressures that would not have been there without humans. I feel fortunate to live during the time that I do, that I had a chance to see a glimmer of what Hawai`i was really like. Of course, I don't know an ecologist there who doesn't wish we could go back in time a couple hundred years before Europeans came, or even a couple thousand years before humans were there at all. We have to be content with the few slivers of the real Hawai`i that are left, and do our best to protect them, although the future looks bleak. When I am in the Alaka`i Swamp, I forget about the continuing destruction below me. As I peer through the mist, all I think about is the wonder of evolution.

For more about the moths and plants of the Alaka`i Swamp, click here.

Labels: environment, evolution, Hawaii, invasive species

Although Walking the Berkshires beat me to it, I'm still going to put in my two cents about the latest problems plaguing beekeepers these days. After all, I am a hymenopterist (lover and researcher of the order containing ants, wasps, and bees), and I hobnobbed with scientists at the U.S.D.A. Bee Lab in Tucson when I lived there.

One scientist at the lab (no longer there) was Steve Buchmann, who advocated tirelessly for the study of the use of native bees as pollinators. Clearly one reason why this idea hasn't taken off is that native bees probably can't ever be big business, because they are (as far as I know) all solitary rather than social. This means you can't keep several thousand in a box and lug them around.

But even hardworking honeybees are not just a bunch of equipment. They are living organisms that have basic biological needs. The idea that we are just pushing the colonies we have left too far is an intriguing one. The reason bees are overextended is that there are too many disease pressures on them now, especially the notorious varroa mite. Certainly being trucked around the country to work isn't something bees' evolutionary history prepared them for.

Here's one site that claims we aren't as dependent on honey bees as we think. Note that it is from a vegan site advocating that vegans avoid honey, but it makes some valid points about problems with having a large dependence on a single alien species.

Perhaps an answer to the problem would be the use of "Africanized" (a.k.a. "killer") bees. Beekeepers from South America to Mexico have had no choice but to use these, because they always take over as they spread. Africanized bees were introduced to the Americas in the 1950's when researchers in Brazil hybridized African and European honeybees, hoping to create a super pollinator. Not only did they actually create a super agressive hybrid that is hard to handle, but of course the bees escaped and have been making their way north ever since. They have created problems for many native American bees along the way, able to outcompete them for resources in some areas. They are moving northward in California, so perhaps there will be enough wild colonies there soon to do the job.

Bottom line: when domesticated honeybees are around in droves, they may push competitors out. I'm betting the void will be filled, if not by wild Africanized bees, than by all the natives out there that just want a chance at their slice of the pollen pie.

Labels: bees, invasive species, USDA