Not your average bovid; the Saiga

13 08 2007

Gazelle
A Mhorr Gazelle, a subspecies of Dama Gazelle, on a cold February morning at the Philadelphia Zoo

Gerenuk
A male Gerenuk, taken in the summer of 2006 at Disney’s Animal Kingdom Park

When I think about antelope, something like a Thompson’s Gazelle, Gerenuk, or Dama Gazelle most immediately comes to mind, countless nature documentaries featuring the bovids in such numbers that they are almost easy to ignore as scenery (or as merely prey for the big cats and other carnivores). There is at least one antelope, however, that would make anyone do a double take; the Saiga (Saiga tatarica).

Saiga
A Saiga, Saiga tatarica, from Wikipedia.

By all accounts the Saiga is quite distinct from its cousins on the African plains. Preferring steppe, semi-desert, and desert habitats, the Saiga is known from Eastern Europe through Mongolia, their conspicuous nose warming air coming into the body in the winter and filtering out dust during the summer. While this aspect of the Saiga’s adaptation is certainly fascinating, it is the horns of the animals that have brought it the most attention, however, as well as the most trouble. As I noted in a post about antlers, horns, and sexual selection, research has shown that males and females of bovid species (which includes antelope) that use their horns as defense against predators both have horns, the horns prevented from getting too gaudy in males because they need to retain their defensive function. In the case of the Saiga, only the males carry horns, and this allows for the horns to become relatively large, and this has greatly contributed to the decline of the species.

Saiga
A male Saiga, from Sokolov, Mammalian Species, No. 38, Saiga tatarica (May 2, 1974), pp. 1-4

One of the primary problems that conservation officials face in Africa and Asia today is the poaching of animals for certain parts of their anatomy for use in Traditional Chinese Medicine (TCM), or other ritual aspects of a particular culture. To understand why the Saiga is targeted for its horns, however, we need to first look at the problems with rhinoceros poaching. Rhinoceros horns have long been treasured by various cultures, young men in Yemen traditionally carry a dagger for defense called a jambia, and there is no better material for the handle of this weapon than rhino horn. Initially, the amount of rhino horn taken was mitigated by the poverty in the region, only the most affluent families being able to afford a jambia with a handle made of genuine rhino horn. As oil prices went up, though, Yemen (among other countries) was flooded with income from the sale of fossil fuels, and the demand for rhino-horn-handled jambias skyrocketed.

Jambias are not the only reason rhinos have been slaughtered. In addition to various ornamental products, rhino horn is valuable in TCM as a fever-reducer. When actually tested it seemed to reduce fever in rats, and Saiga horn had about the same efficacy, although author Richard Ellis rightly notes in his book No Turning Back that “Asprin and ibuprofen, for which no animals have to die, would probably work just as well.” In India rhino horn was used as an aphrodisiac, but expensive prices caused practitioners to stop prescribing it. These pressures, along with others, ultimately drove the rhino population down so low that horns were rare even within illegal trade, and demand kept going up. A substitute had to be found.

The horns of the Saiga, the species only recently recovered from population declines in the early to mid-20th century, were actively endorsed by the World Wildlife Fund as a substitute for rhino horn (also see here and here. Strangely, while the WWF is one of the groups responsible for the crash of Saiga populations, they make no mention of their actions on their website, their efforts of helping the Saiga since 1994 being extolled rather than their responsibility for the near-eradication of the animals. Nevertheless, the political destabilization of Russia and other areas in which the Saiga lived made regulation near impossible, and while some researchers claim that the plains were once “blackened” with Saiga, there are probably less than 50,000 of the animals left throughout their entire range (the Mongolian Saiga, a subspecies, being reported as having a population of less than 1,300 in a 1999 paper by Lushchekina et al. in the journal Oryx).

Indeed, the tale of the Saiga is one of the greatest tales of ecological mismanagement in history, and its implications can still be felt today. Ellis, again in No Turning Back, tells us how it is unlikely that Saiga were as well-established by the time the WWF endorsed hunting Saiga as some conversationalists claim;

By the time of the Soviet Revolution, there were only a few thousand saigas left. To forestall their total eradication, the Soviets protected them in Europe in 1919 and in Soviet Central Asia in 1924. In the 1950s commercial harvests of saigas by local groups began.

Strangely, Saiga was not especially well-established in TCM until recently. Earlier texts like the 1597 text Chinese Materia Medica having no mention of the Saiga, but the 1989 Rare Chinese Materia Medica, and the ground-up horn of the male Saiga can be used to;

…check hyperactivity of the liver and relieve convulsion, treat the up-stirred liver wind, infantile convulsion and epilepsy; calm the liver and suppress hyperactivity of the liver-yang; it is efficacious in the treatment of dazzle and vertigo due to hyperactivity of the liver-yang; it improves acuity of vision, cures headache and conjuctival congestion; clears away heat and toxic material; and can be used to treat unconsciousness, delirium, and mania in the course of epidemic febrile disease.

So it does seem that the Saiga has been a more recent alternative to other traditional remedies, gaining the status of an “ancient treatment” only towards the end of the last century (although I am no expert on TCM and there could be earlier references than the ones mentioned by Ellis). As you probably have guessed by now, though, the major problem in Saiga conservation is that it is the males who are constantly targeted, much of remaining populations being females. This greatly reduces the amount of offspring that are likely to be produced, as well as marking a steep drop-off in genetic diversity and possibly even fitness in the species, the Saiga going through two near-extinctions in less than 100 years.

Saiga
Male Saiga skull. Note the large shelf in front of the large nasal opening. From Sokolov, Mammalian Species, No. 38, Saiga tatarica (May 2, 1974), pp. 1-4

While the earlier near-extinction of the Saiga typically gets less attention than the more recent run on their horns, I feel that it echoes recent policies in the United States to remove wolves and other animals from protection; when stocks seem to approach levels that are barely adequate, many want to open up hunting again when the animals should actually be left alone to reestablish themselves and their genetic diversity. While some are optimistic about the recovery of Saiga, I do not share the same hope that they do. Even if raw numbers of Saiga continue to rise, I worry that the decreased genetic diversity will make them more susceptible genetic problems caused by inbreeding and disease epidemics, one “bad day” in an ecological sense being able to wipe the species out.

I would be remiss, however, if I attributed the problems of Saiga conservation entirely to hunting. As I just suggested, disease and parasites can be an important factor in terms of whether populations die off or not, something that can not be planned for by merely making sure there is more of the animals next season. In 1992, Dukes, et al. published a study that showed that paratuberculosis (or Johne’s Disease) was transmittable from domestic sheep to captive Saiga and back again. Even more recently (Morgan et al, 2005) it has been found that Saiga pick up many of the parasitic worms that also infect grazing livestock along their range, both suffering from the parasites and also allowing them to spread further. Global climate change may also adversely affect the Saiga, the Saiga depending on local climatic cues to dictate their migrations. Heavier snowfall/harsher drought may cause them to have to move to new habitats or be decimated, and at present it is unknown whether they’d be able to cope with ecological changes associated with the current warming trend.

In all, things are not looking too good for the Saiga. While there has been a ban on the trade of products made from them and conservation agencies are trying hard to preserve this species, I believe that it not exists in a weakened state, which (despite population size) will make it more susceptible to extinction. Given enough time the species may recover fully, but in my own view this has “heath hen” written all over it, a species that seemed to recover until disease, predation, and weather changes were too much for the remaining birds in New England to handle. I am not suggesting that we say the Saiga is a lost cause; far from it. What I am recommending is that we actually learn something from the terribly mistakes we’ve made with this species, and stop thinking that merely because populations increase it somehow equals immediate species stability.





Curioser and curioser… AFM wants me to blog about DDT

8 08 2007

I wonder if anyone else received a similar e-mail that just arrived in my inbox; Philip Coticelli of the group Africa Fighting Malaria mentions a new study that has come out in PLoS ONE called “A New Classification System for the Actions of IRS Chemicals Traditionally Used For Malaria Control.” The message I received featured the headline “DDT Highly Effective Against Resistant Mosquitoes: New study recommends using DDT to control #1 killer of African children: malaria,” so where the AFM stands on DDT use seems pretty clear.

I assume I was contacted because I mentioned how National Geographic made some errors in their cover story on Malaria over a month ago, although Bug Girl and Ed Darrell are probably much more capable bloggers to handle this one. Still, when I get the chance I’ll have a look at the article and write up some thoughts, despite that fact that even if DDT has proven effective against mosquitoes thought to be resistant, the efficacy of the product doesn’t assuage my concerns about its toxicity.





A different kind of White Shark

8 08 2007

Australia is known for its populations of Great White Sharks (Carcharodon carcharias), but this week news broke of a different “white shark”; a male Grey Nurse (or “Sand Tiger,” Carcharias taurus, as we call them stateside) Shark that is entirely white.

White Nurse
An image of the all-white male shark, from The Daily Telegraph.

Normally these sharks, like many others, exhibit the classic “dark on top, white on bottom” counter shading, with some darker spots over the dorsal half of their body, but this one is being heralded as “albino.” Albinism is a genetic disorder by a lack of pigment in the hair, skin, and eyes of mammals, the eyes appearing red because there is no pigment in the eye to “cover up” the blood vessels in the back of the eye (we’d all look this way if we lacked pigment in our eyes, which actually occurs every now and then). What is more likely is that this is a shark exhibiting Leucism, which is caused by a reduction in all kinds of skin pigment (albinism just deals with melanin). While I’m not sure what an albino shark’s eyes would look like, the eyes of the shark in the picture seem to be no different from those of normal sharks, which is characteristic of Leucism rather than Albinism as well. Perhaps the most famous examples of leucism are alligators; they appear to be a creamy-white color with blue eyes, almost like giant versions of a white-chocolate alligator I once received as a treat when I was younger.

Still, the presence of such a shark does raise some interesting questions. It seems to be more skiddish than other sharks of its kind nearby, so did its bright coloring make it more attractive to predators (i.e. larger sharks), requiring it to be more shy? How did it get to grow to such a size if it was so conspicuous? Why hasn’t it been seen previously? Why hasn’t another case been seen previously? We might not be able to get answers to any of these questions, but the presence of a potentially leucistic shark is definitely exciting.





Eugenics, re-framed

1 08 2007

Perhaps the most anticipated book of this past summer (other than the conclusion of the Harry Potter series) was Michael Behe’s Edge of Evolution, which was universally panned by reputable scientists and didn’t seem to make much of a splash at all. I didn’t expect there to be anything especially groundbreaking or novel in Behe’s work, and although I’m sure ID folk will be citing it for some time, it hardly succeeds in it’s task of demoting evolution. It was much to my surprise, then, to find out that there’s another book full of potential woo dressed up as science coming out in a few weeks, John Harris’ Enhancing Evolution: The Ethical Case for Making Better People.

As much as I would like to withhold judgment until I actually get a chance to read the book, I have to say that the synopsis and early supporting reviews scream “EUGENICS!” at me, even though I’m sure the author and his supporters are careful not to use the “e” word. According to the inside cover, the book is based off of a set of lectures given by Harris (“the Sir David Alliance Professor of Bioethics at the University of Manchester School of Law”) at Oxford last year. Here’s the summary currently available via the amazon.com page;

Decisive biotechnological interventions in the lottery of human life–to enhance our bodies and brains and perhaps irreversibly change our genetic makeup–have been widely rejected as unethical and undesirable, and have often met with extreme hostility. But in Enhancing Evolution, leading bioethicist John Harris dismantles objections to genetic engineering, stem-cell research, designer babies, and cloning to make a forthright, sweeping, and rigorous ethical case for using biotechnology to improve human life.

Human enhancement, Harris argues, is a good thin–good morally, good for individuals, good as social policy, and good for a genetic heritage that needs serious improvement. Enhancing Evolution defends biotechnological interventions that could allow us to live longer, healthier, and even happier lives by, for example, providing us with immunity from cancer and HIV/AIDS. But the book advocates far more than therapies designed to free us from sickness and disability. Harris champions the possibility of influencing the very course of evolution to give us increased mental and physical powers–from reasoning, concentration, and memory to strength, stamina, and reaction speed. Indeed, he supports enhancing ourselves in almost any way we desire. And it’s not only morally defensible to enhance ourselves, Harris says. In some cases, it’s morally obligatory.

Whether one looks upon biotechnology with hope, fear, or a little of both, Enhancing Evolution makes a case for it that no one can ignore.

As Jeff Goldblum (as Ian Malcolm) said in Jurassic Park, “The lack of humility before nature that’s being displayed here, uh… staggers me.” The phrase “a genetic heritage that needs serious improvement” especially set off warning claxons in my head, and even if Harris himself doesn’t fully commit to eugenics in this area, it seems that the grounds would become ripe for it. Also note how it isn’t stated who, exactly, would be receiving all these beneficial treatments or how such “improvements” would be extended to the majority of the world’s population that cannot even afford simple medicines, much less eugenic treatment regimens.

The idea that we can somehow improve humankind through our understanding of science (“better living through [bio]chemistry,” if you like) is hardly new, and even in such works as G.G. Simpson’s The Meaning of Evolution the author hints at a time when we may be able to guide our own evolution, though the means during the time the book was written and revised (early 1950’s) were lacking. Even though we have come a long way since that time, I sometimes have to wonder if we even really understand what we’re messing with when we consider cloning. I don’t know how scientific this new book is going to be, but the synopsis makes it sound like through eugenic breeding or medical innovation we can reach some sort of Platonic ideal where everyone is beautiful, healthy, and intelligent, living a long and happy life. HIV/AIDS and cancer are mentioned as two diseases that we may be able to eliminate, but somehow I doubt that all disease would just disappear because we engineered ourselves a different way, and if there were lots of human clones, lack of genetic diversity could make populations more susceptible to disease.

While Harris may be able to tackle some of the superficial ethical objections in the book, I doubt that he fully considered or deconstructed the more functional objections, mostly being that it seems that trying to improve ourselves would probably make the human species weaker, not stronger, as well as leading to some unsavory (and dangerous) social/political consequences. I probably won’t be able to check this book out immediately when it is released on the 17th, but I’ll be interested to see the reviews of any other science bloggers if they get the chance to read it.





Thursday Book Notes

26 07 2007

Last night I finished Our Inner Ape, and to be honest I didn’t find it especially impressive. It reminded me a bit of other pop-sci books dealing with animal intelligence like Inside the Animal Mind (the companion volume to the PBS special) where anecdotes were put forward without much else. While I think behavioral observations have a lot to tell us and point to more animals being merely a bundle of behaviors that must always be spoken of in the passive voice. Still, de Waal takes his observations of chimpanzees and bonobos in captivity and takes them to be the rule, extrapolating from them his main thesis; humans are a “Janus Head” that combines the aggressiveness (even at times bloodthirstiness) of chimpanzees and the more social/sexual habits of bonobos. de Waal does note that each species works on its won continuum and rightly notes that despite notions like American individualism we are a highly social species (one of the worst punishments is isolated confinement or banishment), but he seems to present a bit of a false dichotomy between chimpanzees and bonobos, clearly favoring the bonobos. Even though de Waal does temper his statements, he definitely presents chimpanzees as more vicious and bonobos as more peace-loving (something that is becoming contested as we observe bonobos in their own habitat), he clearly favors the bonobos as an ancestral model for our behavior. In any case, I could understand what de Waal was trying to get at in the book and it does have some good content, but I think that what’s good in it gets mired down by the false “Janus Head” dichotomy that is the main theme of the work. A Primate’s Memoir remains the best popular book on primates I’ve read yet.

I also got halfway through Survival of the Sickest before passing out, drooling on my pillow (it wasn’t so much an effect of the book as it being a late hour when I was reading it). It’s a short work, only about 200 actual pages before the glossary/notes/bibliography with larger spacing and font than I’ve seen in other books, so it was easy to get through the first 100 pages in a short amount of time. As for the content, there is some very interesting material in the book (like how inheriting a disease that keeps iron in the body locked up may have helped some people survive the bubonic plague), but I don’t care much for the style. As I opined to my wife, it’s the “Mountain Dew of pop-science books.” The overall strategy in the chapters is to present a reader with a particular medical dilemma, then spend a few pages going back to its roots, only then to return to the original topic and sum up the significance of everything. This isn’t a bad strategy, but it’s a bit overused in the book. The writer throws in plenty of pop references in an attempt to make the book more accessible to those not familiar with science, but overall I just felt that the rhetorical strategies were annoying and even showed a lack of respect for the reader. It’s written in something of a fast-paced MTV style, and while I get the impression that writers like Gould and Sagan respected the intelligence of their readers, I get the feeling from Survival of the Sickest that I’m only supposed to be dazzled and little else. The writer is also at their best when discussing genetics and medicine, forays into geology (and as I wrote about earlier, human evolution) are typically marked by misunderstandings or misrepresentation. I don’t have a problem with the actual content/premise of the book, but the style in which it is presented doesn’t appeal to me at all. Looking at the amazon.com reviews of the book, however, I guess I’m in the minority, and perhaps it could serve as a fair primer for people unfamiliar with evolution (just make sure they read some more accurate books, too!).

After I finish Survival of the Sickest tonight I’m not sure what I’ll be on to next. I have a stack of books next to the couch (and I still need to finish A Cold Look at Warm-Blooded Dinosaurs), but I do want to read Demonic Males and Forley Mowat’s Never Cry Wolf in the near future as well. On top of that I still have to read my books by Cope, Mantell, and Darwin, so I definitely am not suffering for lack of options. Then again, I should probably start Quammen’s Song of the Dodo now that my wife has finished it, going through it chapter by chapter so I can pin down any mistakes as Bora had suggested so long ago. At least I’m petsitting this weekend so I’ll have all day Saturday to feed my mind.





New England Journal of Medicine Peddles Kitty Woo

26 07 2007

In the latest edition of the New England Journal of Medicine, out today, there is a new “Perspective Article” entitled “A Day in the Life of Oscar the Cat.” It is clearly a puff piece, describing how a resident cat named Oscar at Steere House Nursing and Rehabilitation Center in Providence, Rhode Island curls up to patients that only have a few hours to live. The tone of the article is a bit more mystic however, suggesting that Oscar sniffs the air in order to figure out when someone’s “time” is, acting like a feline Grim Reaper (although to the best of my understanding Death does not purr and nuzzle those about to die, despite his well-known fondness of cats).

Still, the fact remains that this particular cat has attended 25 people who died shortly after Oscar curled up to them, and the cat generally ignores other people. This has led Yahoo! to put the story “Oscar the cat predicts patients’ deaths” on the front page, referring to the NEJM article as if it were some kind of new paper or research. The only real rationality in the Yahoo! story is found in this quote;

Nicholas Dodman, who directs an animal behavioral clinic at the Tufts University Cummings School of Veterinary Medicine and has read Dosa’s article, said the only way to know is to carefully document how Oscar divides his time between the living and dying.

If Oscar really is a furry grim reaper, it’s also possible his behavior could be driven by self-centered pleasures like a heated blanket placed on a dying person, Dodman said.

Still, I’m sure plenty of people will latch on to the story as proof of psychic connections with animals, ESP, and other woo despite the fact that an observation has been made but no actual research has been done. I’m not even sure if there have been any studies about how animals react towards the sick or dying, although there is plenty of anecdotal evidence to suggest that pets can pick up on signs that we may miss (my parents’ dog knew my mother was pregnant with me before she did, at least that’s how the story goes). Hopefully someone will have a look at this case and determine what is actually going on, but I have the feeling that even if such a study was undertaken many people would ignore it in preference of ideas about special connections with animals.

Update the 1st: Aydin brings up something I didn’t think about at first; maybe Oscar’s actions are a variation on those of Clever Hans the horse. For more, visit Snails Tales.

Likewise, Julia pointed me to a BBC article where it states that Oscar becomes quite upset if he’s removed from the room. This is likely an important clue, and (as morbid as it sounds) maybe there is some sort of chemical/pheromone/scent or something else about the dying that attracts this cat. It would explain the behavior of selecting and being affectionate with those who are about to pass away. Hopefully someone will look into this, and I’d love to see if a reason could be found for Oscar’s behavior.





Freudian Field Day; 10 Idiotic Assertions in Psychology Today

10 07 2007

Update: Bora had kindly put together a short-list of other bloggers who have addressed the intellectual poverty of the article. Have a look here.

There’s been a little bit of a stir in the blogosphere in reaction to a recent evolutionary psychology article entitled “Ten Politically Incorrect Truths About Human Nature” that showed up in Psychology Today. I honestly am not terribly familiar with evolutionary psychology outside of how contentious it is (scientists like Niles Eldredge and Ian Tattersall, among others, regarding it as junk science), but at the moment I suppose I take something of the middle ground; our evolution certainly affects our mind today, but figuring out what has and has not changed is the trick. Case in point, I recently watched the first few installments of the BBC program The Human Face hosted by John Cleese. In the discussion of professional models, it was said that a particular look that models can give works so well because it is basically the face that women make before orgasm, so we’re naturally more attracted to such a face. I really have no idea if this is true, and overall it seems a bit too simplistic to me; everyone doesn’t just go helpless with euphoria when we see such an image (at least, I know I don’t). In any case, I’ll be going through the 10 assertions the authors of the Psychology Today list, giving my thoughts on each.

1. Men like blond bombshells (and women want to look like them)

One of the first things that strikes me about this article is that it isn’t especially tentative nor does it back up it’s sources; things are simply said to be as they are and we’re expected to believe what the authors are saying is true. Beyond that, the general hypothesis is that blond women remind men of young women, young women with large hips and a small waist being able to be better reproductively, and therefore they are more desirable sexually. On top of that, large breasts are supposed to be good age indicators, the amount of sag telling males how old the woman is. This, I must say, just sounds stupid; surely there are better indicators of age than breast size in relation to “sag”, and while I’m not an expert, isn’t there a large amount of natural variation in female chests anyway? The authors seem to be confusing correlation with causation, raising a “just-so story” to the level of fact. Likewise, their discussion of blue eyes sounds equally dubious;

Women with blue eyes should not be any different from those with green or brown eyes. Yet preference for blue eyes seems both universal and undeniable—in males as well as females. One explanation is that the human pupil dilates when an individual is exposed to something that she likes. For instance, the pupils of women and infants (but not men) spontaneously dilate when they see babies. Pupil dilation is an honest indicator of interest and attraction. And the size of the pupil is easiest to determine in blue eyes. Blue-eyed people are considered attractive as potential mates because it is easiest to determine whether they are interested in us or not.

This seems more of a reaction to modern eye color variations (which can be artificially achieved through contact lenses) than the effects of something evolutionary; I doubt there was a bias in our hominid ancestors towards blue eyes (if blue eyes were even common enough then). It also raises the question of blue eyes in populations where they nearly never occur today; is there any significant change in attraction to an individual solely because of eye color? What is people just like the color blue, or like blue eyes because they are unusual? The authors don’t put forth any alternative hypotheses.

2. Humans are naturally polygamous

The first thing that irked me about this discussion is that no distinction was made between what science may or may not tell us and morality, i.e. that whether our species was polygamous throughout our evolutionary history does not dictate whether it is good or natural today. As for the argument itself, the authors point to the mild sexual dimorphism between men and women and suggest that bigger, stronger males monopolized the females, females also preferring big and strong males. No alternate hypothesis was given for the variations, nor was it mentioned that it is unlikely that only the biggest, strongest men mated. Thinking back to what I’ve come to learn about sexual selection and the book A Primate’s Memoir, a hyper-masculine male may be highly aggressive (even abusive) in addition to being the biggest and strongest, and just because one male tries to monopolize all the females does not mean that other males never get the chance to mate (less privileged males may keep up longer term relationships with females and produce offspring surprisingly often).

3. Most women benefit from polygyny, while most men benefit from monogamy

Continuing with their assertion that it’s better for females to share a wealthy man (or, in terms of past history, one that can provide protection), the authors assert that monogamy benefits men because a “poor” wife is better than no wife at all. Again, outside of “protection” the authors make no qualifications as to what females actually benefit from sharing a dominant male, and polygynous mating structures do not necessarily guarantee the safety or well-being of the females. While it might be true, in a thought experiment, that less-masculine males would benefit more from a monogamous or polyandrous mating structure than a polygynous one, the authors provide no evidence to support their claim and the overall reasoning is rather shallow.

4. Most suicide bombers are Muslim

The title seems more like a matter of statistics (I wonder if they considered Kamikaze pilots during WWII), but the authors contend that Muslim men are engaging in terrorism to quench their sexual desires. Rather than being a product of religious brainwashing, the authors assert that Muslim suicide bombers are primarily doing it so they can receive 72 virgins when they arrive in heaven. They show nothing to support this at all, nor do they look at the motives of suicide bombers from other cultures and time periods. The authors case is highly dubious, at best.

5. Having sons reduces the likelihood of divorce

Once again, the authors don’t do much other than say “This is how it is, deal with it.” No statistics are given as to divorce rate, family makeup, etc., and they try and make the case that since fathers must pass their wealth and power onto their sons they are more likely to stay involved in the family. This model seems to assume that the family has only one child that is the “heir” to his father’s legacy, and overall it seems like it has more to do with culture than “evolutionary psychology.” Indeed, the model assume that the son actually inherits wealth and power from the father, but no qualification/quantification is made of what this would look like (i.e. making sure the son gets through college before divorcing?)

6. Beautiful people have more daughters

The authors contend that because males have historically been privileged and promiscuous, they produced more sons that went on to become privileged themselves, a kind of artificial selection for males that would cause a higher ratio of males to be born than females. Little is said of infanticide or males being favored over females in families, so once again the authors seem to connect two dots to make a line without trying to plot any more points to see if the results make sense.

7. What Bill Gates and Paul McCartney have in common with criminals

This one might have a grain of truth to it, but once again it is lost because the authors reduce everything to sex. Using Bill Gates and Paul McCartney as examples, the authors contend that much like Jackass-like feats of stupidity and crime, male “genius” tends to peak at an early age. Why? Because we all want to bad to impress women. Even if we were to argue that artists, scientists, musicians, etc. stayed active and creative all through their lives, the authors argue that the “best work” of all these men occurred early on in their lives because they were in competition to secure notoriety in order to obtain a mate. I wonder what Charles Darwin would say to them about this. I found the last few sentences of this point especially wanting;

Women often say no to men. Men have had to conquer foreign lands, win battles and wars, compose symphonies, author books, write sonnets, paint cathedral ceilings, make scientific discoveries, play in rock bands, and write new computer software in order to impress women so that they will agree to have sex with them. Men have built (and destroyed) civilization in order to impress women, so that they might say yes.

Yes, nothing gets women hotter than developing a new computer language or studying the flavors of quarks. While “male conquest” may have been significantly evidenced in the past, the authors don’t think about the societal context in which many men (especially within the past few centuries) create their “great works.” Can it really be all about sex and have nothing to do with having to establish oneself in science, art, etc. or other factors like an openness to new ideas? I don’t want to sound overly idealistic and I’m sure (especially in the realm of modern music) that sex does have a part to play here, but I would hardly argue that all of male artists, musicians, scientists, and writers were only driven by their sexual desire, their intellectual prowess declining as their desire did.

8. The midlife crisis is a myth—sort of

This point was a bit odd; men go through a mid-life crisis because they desire to replace their menopausal wives with a younger wife, once again having sex trump every other potential factor. Because the authors are so sex-obsessed, the “mid-life crisis” is said to have nothing to do with a man wanting to reclaim his own youth or get a “do-over,” but instead he just wants a woman along the lines of the one discussed in asinine assertion #1. I’m certainly not an expert on the “mid-life crisis” but reducing it to sex does a disservice to a complex issue.

9. It’s natural for politicians to risk everything for an affair (but only if they’re male)

Here the authors again make the assertion that every male would have sex with as many women as possible if it were feasible to do so, the primary reason for obtaining a political office being gaining sexual power (have a look at the Washington Monument; what are trying to say to the world?). This seems to run counter to their assertion that influential men do their most important work while young while being potentially in-agreement with or counter-to their “mid-life crisis” argument depending on the age of the man and his marriage. We should fully expect powerful men to try and have sex with as many women as possible, they say; why should we expect otherwise?

10. Men sexually harass women because they are not sexist

The last point is a bit confusing; men abuse and intimidate other men, so why should they treat women any different? Men try to achieve power through competition in the workplace and once they have that power they try to use it to get women to sleep with with in one-night-stands, women taking great offense to the despicable male behavior. The authors make no distinction between abuse/intimidating/hazing etc. amongst men in competition and they way they treat women at work (nor do they say that such behavior is unacceptable), sex being the most important factor in their view.

While the authors of this may have had a few inklings of insight, it was all lost in a flood of male sexuality that seems like an attempt to justify sexually motivated aggression on the part of males. Women are not considered outside their roles of sex objects that males strive to obtain, giving the whole article (and probably the book the article promotes by the same authors) of rather lop-sided view. If this is the best evolutionary psychology has to offer, than I would have to join others like Niles Eldredge who regard it as worthless and even dangerous. It would be foolish to say that our evolutionary history has not influenced the way we are today, but asserting that such selected behaviors dictate the whole of the human experience, that sex rules all and we cannot hope to ever escape our desires, cheapens us all. As much as I disagree with much of what the authors of this article wrote, I could have at least given them some points for mentioning that finding out reasons behind certain behaviors should not endorse immoral or otherwise despicable actions, but the authors of this study would rather tell men that they’re pre-programmed sex maniacs than try and do anything constructive.





Birds pick up a good smoking habit

6 07 2007

If you should ever find yourself at Exeter St David’s railway station in Devon, England, pay close attention to what happens when someone flicks away a burning cigarette. While it may very well get stepped on, kicked onto the tracks, or otherwise snuffed out, if you are at the station during a quiet period you may just see something phenomenal; birds that fumigate themselves with the used butts. In an article issued a few weeks ago in the Telegraph, Rooks (Corvus frugilegus) were observed picking up still-smoldering cigarettes, moving them to a more private location, and opening up their wings to collect the smoke. The intelligence of Corvid birds (crows and their relatives) is well-known, although this is perhaps the first time that these birds have been seen taking advantage of discarded suicide sticks to benefit themselves, probably in an attempt to kill parasites living on their wings.

When my friend Molly first sent me the article (hat-tip to Molly) a few weeks ago, the first thing that came to my mind was the behavior known as “anting.” Although I had never studied it in detail, I remembered that some birds pick up ants and rub them on their feathers, the formic acid the ants secrete in an attempt to defend themselves having a detrimental effect on the parasites living on the bird (as suggested by Kelso and Nice’s “A Russian Contribution to Anting and Feather Mites“). In fact, the first mental image was of a crow, holding a smoking cigarette in its beak, rubbing the ashes over its wings. As the article makes clear, however, this is not the case and it is not merely an example of the birds doing an old behavior with a new tool; they have done something that appears to be entirely new.

Still, I thought I would look into anting behavior a bit more; the benefits to birds that exhibit the behavior are clear, but stopping inquiry there would be rather adaptationist, claiming that birds do it because it benefits them, but why birds engage in this behavior at all might not be as straightforward as it seems. In a 2004 paper entitled “Bactericidal and Fungicidal Activity of Ant Chemicals on Feather Parasites: An Evaluation of Anting Behavior,” Revis and Waller found that the bacteria Bacillus licheniformis, Bacillus subtilis, and fungi Chaetomium globosum, Penicillium chrysogenum, and Trichoderma viride were not inhibited by the natural concentrations of chemicals excreted by several species of ants (although concentrated formic acid did work), suggesting that the ants selected simply did not contain concentrated-enough doses of formic acid to provide the birds protection against the bacterial and fungi tested in the study. This is surprising, especially since tests don’t seem to support the idea that anting inhibits arthropod parasites either, yet the birds keep on exhibiting the behavior. Why?

What is often left out when anting is discussed is that the birds often eat the ants, supposedly getting a “two-for-one” kind of benefit from picking up ants. This could give us a clue to the real motive behind anting, however, and although I do not have access to the article, Judson and Bennett (1992) hypothesized that anting may actually serve to remove toxic formic acid from ants prior to ingestion. From the abstract to their paper “‘Anting’ as food preparation: formic acid is worse on an empty stomach“;

Anting is a behavior common among passerine birds, yet its function is unknown. The behavior consists of a highly stereotyped set of movements which start when a bird picks up an ant, usually one which sprays formic acid as a defense, and sweeps it with frenzied motions through its feathers. The bird will often also eat the ant. As formic acid is toxic, we have tested the food-preparation hypothesis, that is, that the birds are anting to remove a distasteful or toxic substance from the ant before eating it. In a pair of experiments on starlings, Sturnus vulgaris, we have found evidence in support of this hypothesis.

[Again, I don’t have access, but for information on the toxicity of formic acid to birds see Bennett, Llloyd, and Cuthill’s 1996 paper “Ant-derived formic acid can be toxic for birds.” It should also be noted that it is sometimes difficult to tell whether some birds eat or discard ants after using them in anting behavior, as described in Osborn’s “Anting by an American Dipper (Cinclus mexicanus)]

Indeed, anting behavior doesn’t always include ants, and the observations of birds “anting” with various other insects seems to support the notion that the birds are ridding their prey of noxious chemicals rather than trying to kill their parasites. One such example is described in Eisner, et. al’s “Pre-ingestive treatment of bombardier beetles by jays: food preparation by ‘anting’ and ‘sand-wiping’,” where Blue Jays subject bombardier beetles to anting prior to ingestion, making sure that they don’t get a stomach full of toxic chemicals. The study notes that the jays used in the tests did not always “ant” with the beetles, however; sometimes the beetles were repeatedly pecked, dropped, and picked up again before being consumed (“pre-milked” beetles were pecked and eaten quickly, so the “peck until the beetle is done discharging” seems like the primary way of handling the beetles). Snails, berries (VanderWerf, 2005), and caterpillars (Wenny, 1998) have also been observed being used during anting by birds, but in each of these three cases the prey was not eaten (or did not appear to be in the case of the caterpillar). These bouts of anting were followed by preening, suggesting that there perhaps there is some benefit to the chemicals present in all three organisms to the bird, although we cannot be sure of what. The incident that VanderWerf is even more interesting as the event was witnessed on one of the Hawaiian islands, where ants, the snail, and the berry are not native and the bird (the ‘Elepaio or Chasiempis sandwichensis) is non-migratory. This shows that even though ants are most commonly associated with anting, the behavior can incorporate a variety of different resources and is not restricted to species that come into contact with ants on a regular basis.

Animals other than birds exhibit anting behavior, however; just this year Verderane, et al. published “Anting in a Semifree-ranging Group of Cebus apella,” describing how one particular species of Capuchin monkey rubs ants all over its body, a behavior that correlates with the seasonal incidence of an ectoparasite. This, the researchers conclude, is true anting and actually does work on the pests in the primate’s fur, whereas the benefits of anting in birds (where it was first described) is still a bit of a mystery.

Part of the reason why anting is such a mystery is that it involves interactions between hundreds of species all over the world; I don’t know if it’s even possible (or wise) to impose an “always/never” rule on what benefits the birds may or may not be receiving from anting. While the evolution of the behavior likely started by trying to make prey insects expel their noxious chemicals prior to ingestion, it could very well have been co-opted to take advantage of naturally-occurring substances present on other organisms that may positively affect the health of the bird. Depending on where you are, the strength of chemicals in the available ant/organism, and the weaknesses of your particular parasites, anting behavior could be used primarily in terms of food prep or it could indeed have a medicinal purpose; the amount of research into all the existing combinations is staggering.

Anting aside, what the English rooks appear to be doing is something that seems to be more straightforward; I really do think that they are trying to kill the parasites on their wings, although they likely only recognize the unpleasant feeling of being inhabited by parasites and a cessation of that feeling when the smoke their own wings. What I would be interested to see (other than an actual test of this hypothesis) is the potential harm done to the birds respiratory system by the cigarettes they use. While it is true that they receive some health benefits from removing parasites from their wings, are their lungs adversely affected by the smoke in a way similar to ours? This could be a great opportunity for scientists interested in health, behavior, and toxicology to collaborate (it reminds me of one of a study I would like to do, checking the health/cholesterol of animals found in theme parks which sell fried foods vs. the health/cholesterol levels of other populations in cities, suburbs, parks, and forests). Hopefully some research will be forthcoming, but until then I hope keen folks continue to keep an eye out for amazing bird behaviors wherever they are.





Something stinks over at National Geographic…

18 06 2007

Update the 1st: In the interest of being accurate, I’ve posted what the article actually says below. I didn’t have it with me when I originally wrote the post, although there is little different from what I said. Expect a more in-depth post this week when I’ve finished Carson’s book and make sure I understand just what DDT and DDE is doing to people. The author of the article, Michael Finkel, writes;

Soon after the [malaria eradication program collapsed, mosquito control lost access to its crucial tool, DDT. The problem was overuse-not by malaria fighters but by farmers, especially cotton growers, trying to protect their crops. The spray was so cheap that many times the necessary doses were sometimes applied. The insecticide accumulated in the soil and tainted watercourses. Though non-toxic to humans, DDT harmed peregrine falcons, sea lions, and salmon [emphasis mine]. In 1962 Rachel Carson published Silent Spring, documenting this abuse and painting so damning a picture that the chemical was eventually outlawed by most of the world for agricultural use. Exceptions were made for malaria control, but DDT became nearly impossible to procure. “The ban on DDT,” says [Robert] Gwadz of the National Institutes of Health, “may have killed 20 million children.”

Straw man, anyone?
___________________________________________________________________________

As I mentioned this past weekend, the new issue of National Geographic features a cover-story on malaria. Reading over the story last night, the author makes some jabs at Rachel Carson’s Silent Spring (which I should finish tonight) and claims that not only did DDT only effect sea lions, salmon, and peregrine falcons, but that it has no harmful effects to humans, either. The author also included a quote from a researcher (I forget their name, I will include it when I do the final write-up) that says the ban on DDT may have killed 20 million children. I was quote outraged that National Geographic would print such drivel without any further clarification or facts to back up the assertions, so I decided to start looking through the technical literature to see what is known about DDT and organochloride toxicity. I’m going to do a longer write up tonight or tomorrow, but if you’re interested here are some resources you can check so you don’t have to wait for me.

Bug Girl has an entire serious of posts taking on recent attacks on Rachel Carson, Silent Spring, and environmentalists in general. They serve as wonderful primers and are well-worth the time to read;

DDT, Junk Science, and the attack on Rachel Carson
New York Times, DDT, and an asshole
Rachel Carson and Chemical News
DDT, Junk Science, Malaria, and the attack on Rachel Carson
Malarial Drug Resistance: exciting new development!

Wikipedia- Organochlorides: Toxicity
Wikipedia- DDT
[Note: The Wiki DDT page is a bit of a muddle, and you can definitely see the influence of people who do not consider DDT to be harmful at all. I’d skip down to the Effects on Human Health section, although I’d check the sources for the information there as well.]

Also, beware the so-called “100 things you should know about DDT” page (by the contemptible J. Gordon Edwards and Steven Milloy), which is crass enough to show a photoshopped picture of Rachel Carson wearing a shirt that says “DDT: A weapon of mass survival.” What this page is doing on the Wikipedia entry under “Toxicity” I don’t know.

Here is the Scorecard entry for DDT as well, but it seems to be out of date and does not list its sources.

PubMed Abstract – Chronic nervous-system effects of long-term occupational exposure to DDT.
The paper suggests that there are long-term neurological effects among those who have applied the chemical.

PubMed PDF- Concentration of Organochlorines in Human Brain, Liver, and Adipose Tissue
Autopsy Samples from Greenland

Not about DDT specifically, but it does contain interesting information about organochlorines (DDT is one) and how they accumulate in marine mammals and people who eat those mammals.

1999 NJ DEP Fact Sheet – Historic Pesticide Contamination
This page is old, but it does suggest that up to 5% of my home state may still be affected by past use of pesticides like arsenic and DDT

Undated PDF – Peregrine Falcon’s in New Jersey
This page does not list its sources, but it states that DDT was banned in New Jersey in 1968, but use of the product caused a major crash in predatory-bird populations in the state (I also know of anecdotal evidence from an ecologist who helped re-establish ospreys in the Barnegat Bay area)

PubMed Abstract – In utero p,p’-DDE exposure and infant neurodevelopment: a perinatal cohort in Mexico.
Study suggests that DDE exposure during the first trimester of pregnancy may affect developing human children.

Abstract – The human health effects of DDT and PCBs (polychlorinated biphenyls) and an overview of organochlorines in public health
Very general abstract, but does note that some organochlorides do have effects on liver and neurological functions.

PDF Paper – Association of DDT and DDE with Birth Weight and Length of Gestation in the Child Health and Development Studies, 1959–1967
The study did not appear to come up with any strong correlation for male infants, advising that more study is needed.

PDF LEtter – Invited Commentary: Why DDT Matters Now
Summation of two paper appearing in a 2005 issue of the American Journal of Epidemiology. While the letter (and papers) are far from being iron-clad evidence, I did find this admission interesting; “…almost no data are available on the health effects of DDT exposure at the levels experienced by those living in sprayed homes.” In places where malaria is still a threat, the insides of homes are sprayed with DDT and people ingest DDE (either through metabolizing DDT themselves or the environment metabolizing it, which is then ingested). This brings up an interesting point; given the propensity of DDT to concentrate in tissues and be passed along in mother’s milk, over the course of various generations will DDT concentrations in humans go up, and if so, what effect will this have on health?

Paper PDF – Reduced Seminal Parameters Associated With Environmental DDT Exposure and p,p9-DDE Concentrations in Men in Chiapas, Mexico:A Cross-Sectional Study
This Journal of Andrology paper echoes what seems to be the case with DDT and reproductive effects, summed up by the authors as follows; “…nonoccupational exposure to DDT, as assessed by plasma p,p9-DDE concentrations, is associated with poorer semen parameters in men, indicating adverse effects on testicular function and/or the regulation of reproductive hormones.” The percentage of motile sperm went down, tail defects went up, and some suffered incomplete DNA condensation.

Fulltext Paper –THE HUMAN HEALTH EFFECTS OF DDT (DICHLORODIPHENYLTRICHLOROETHANE) AND PCBS (POLYCHLORINATED BIPHENYLS) AND AN OVERVIEW OF ORGANOCHLORINES IN PUBLIC HEALTH
While the abstract states that there is “no convincing evidence that organochlorines cause a large excess number of cancers,” the section on DDT has some interested correlations between DDT exposure and some kinds of cancers.

JSTOR Paper 1st page – DDT and Wildlife
A pre-Silent Spring (1946) paper that seems to dismiss claims of conservationists that DDT is dangerous to wildlife and humans.





Is there a civet in your perfume?

3 06 2007

One of the most curious aspects of dating and relationships in technologically advanced countries is the need for people to cover up their natural scent with lots of different products. For my own part, my current shampoo, conditioner, body soap, deodorant, and cologne are all different, and I douse myself with foreign scents to make sure that I do not offend the olfactory sensibilities of others. But where do such scents come from? There are plenty of synthetic chemicals that mimic naturally (or unnaturally) occurring scents, but, interestingly enough, some fragrances still require animal sources. As Terry Pratchett wrote in The Unadulterated Cat (which ironically sits next to a basket of the products I mentioned above in the bathroom);

Civet

An 1894 Richard Lydekker painting of an African Civet

The civet cat has been a nervous animal ever since it discovered that you can, er, derive civetone* from it and use it in scent. Exactly how this is done I don’t know and do not wish to research. It’s probably dreadful. Oh, all right, I’ll have a look.

It is.+

*A 17-member ring-ketone, according to my dictionary, as opposed to the mere 15-membered muscone from the musk deer. Does the civet feel any better for knowing this? Probably not.

+Who invents these scents, anyway? There’s a guy walking along the beach, hey, here’s some whale vomit, I bet we can make scent out of this. Exactly how likely do you think this is?

Indeed, the civet’s (specifically the African Civet, Civetticus civetta) scent is also useful to those wishing to track big cats, a researcher in a recent issue of Natural History relating that central american jaguars (Panthera onca) are especially drawn to the civetone in Calvin Klein’s “Obsession.” Good to know if you’re in search of big cats, but it still leaves the question of what civetone actually is and why it is important. For that, I turn to Richard Despard Estes Behavior Guide to African Mammals, in which he describes the olfactory communication of the animals;

Olfactory Communication: scent-marking with dung, urine, perineal gland.
Perineal-gland marks appear to be concentrated on trees fronting roads and pathways, especially trees that produce fruit eaten by civets. A passing civet pauses every 85m or so to press the everted gland against a trunk. The secretion is a thick, yellowish grease that hardens and turns dark brown and more visible with age, while the powerful and disagreeable scent remains detectable for at least 4 months. The musk scraped periodically from the perineal gland of captive African civets is refined into civetone, which “exalts” the fragrances of expensive perfumes.

Why not just cut out the middle-man and press a civet’s butt to your arms, neck, or chest? Such is what a cartoon (and rather low-quality article) from the Softpedia article “Get the best perfume from the cat’s a**” portrays. This is not entirely accurate as the civet’s secretions must be combined with alcohol and other chemicals to bring out its “pleasant musky odor,” but this does not change the fact that for centuries fragrance makers have relied on greasy secretion near a mammals anus to produce more pleasant personal scents.

Fortunately, synthetic civetone has been produced, but many “high-quality” perfume manufacturers still prefer scraping a civet’s musk glad the old fashioned way. From Yilma D. Abebe’s “Sustainable utilization of the African Civet (Civetticus civetta) in Ethiopia” (which is also found complete here);

Despite civet musk being produced artificially in the late 1940’s, high quality perfume producers still prefer the use of civetone (Anonis 1997). Demands for a synthetic alternative have been growing in recent years however with the British Fragrance Association (BFA) and the International Fragrance Association (IFRA) of the opinion that perfume industries are more likely to use artificial musk (Pugh 1998).

Indeed, the harvest of “natural civetone” continues, (despite some web sites suggesting that it has stopped with the invention of synthetic civetone) and while the African Civet is not threatened it does not change the fact that cruel practices have been recorded among civet farmers and wild civets are continually caught to replace those that die of stress in captivity (I’ll leave you to imagine why they’re so stressed).

The author also notes that local superstitions and husbandry practices make the trade very hard to regulate and control, and the process is considered unsustainable (although unlikely to stop because of economic gain associated with civet farms). Also of interest is the assertion that predominantly Muslim farmers in Ethiopia harvest civetone from civets. The author writes;

In Ethiopia, only Muslim communities are practice civiculture. According to oral history the legendary leader Nessiru Allah, who lived in Limu, Keffa, suffered from an eye affliction that was cured by an application of civet musk. Once cured, Nessiru Allah ordered followers of Islam to farm African civets (Mesfin 1995).

So what are we to do? Personally, I would check your own perfumes to see if “civetone” is listed in the ingredients, and even contact various perfume companies to see if they’re using civetone derived directly from civets and to ask for a ban on using the harvested secretions from the carnivores. Even if large companies switched over to artifical civetone, however, the practice would likely survive to some degree in Ethiopia and would be resistant to reform, so local and government workers would have to work with the farmers to ensure humane practices (i.e. scraping civet musk off bars or posts they deposit it on rather than sticking a spoon into the animal’s gland) and open up other economic opportunities so that the farmers are not relying on civets for income (even in the IUCN report mentioned above, civetone seems to be bringing in less and less money to Ethiopia). Such is the problem with humane practices and conservation, however; merely establishing the science aspect will not convince the farmer who needs income from his practices, and care for both the animals and people is needed if a positive change is going to be made.

End Note: Civets aren’t the only animals to be farmed for particular scents or secretions; bears and musk deer (also important to the fragrance industry) suffer similar consequences as well, and both will require seperate posts to do their stories justice.

End Note 2: I’ve corrected some of the mistakes I made in the initial post. I started getting a pretty bad migraine in the middle of writing this so I didn’t entirely pay attention to what I was doing. I’ll have some more posts up when I recuperate.