Student Post: More on Gender Dominance–An Evolutionary Psychological Approach

I have some thoughts on the topic of male and female dominance brought up by Blue_Expo.

In fact, it was the topic of a paper for my Evolution of Human Aggression class…

Females are under some different sexual selection pressures than males stemming from the fact that they are the limited sex. They can only produce a finite number of offspring and are heavily invested in their progeny. Perhaps this is the basis for the female dominance social hierarchies observed in bonobos (Parish et al., 1994) and hyenas (Jenks, 1995). In both these systems, offspring inherit their mother’s rank and a mother is willing to engage in physical combat or establish social coalitions designed to elevate their offspring in rank. Because rank determined ability to procure resources, survive and reproduce, and females had high parental investment, there was sufficient evolutionary pressure for females to evolve the capacity to establish dominance even over males on their offsprings’ behalf.

[Read more…]

The Empire is well pleased

You may have heard about the 21-foot long half-scale model of the X-Wing that was built to actually fly, using solid fuel rockets. It was launched yesterday. The results were caught on video, and it is spectacular. There were lots of kids watching this thing, the announcer does the countdown, it lifts off on beautiful columns of flame and smoke, gets about 50 feet in the air … and did the announcer just say “Holy shit!” over the loudspeakers?

The kids are thrilled. We shall enlist them in the Empire’s legions.

I am not defending creationism, I’m defending academic freedom

Moi? Mentioned in the Waco Tribune? Defending a creationist? I knew that remark would come back to bite me. At least the author misspelled my name, so my shame won’t spread too far (except, unfortunately, that I seem to be more widely cited as “Meyers” than “Myers”). Anyway, it’s a letter by Robert Marks’ lawyer, complaining about Baylor’s decision to shut down Marks’ “evolutionary informatics” web page, and I’m mentioned as supporting him.

In Minnesota, where I live, a well-known biologist and faithful believer in evolution, Professor P.Z. Meyers, has followed what Baylor has done and called for it to reverse itself.

Meyers loathes ID and its proponents and blogs about it, frequently with exceptional humor. It is more than telling — shameful, perhaps? — that Meyers, a self-identified atheist, sees something amiss here that those in power at Baylor cannot or will not.

Yeah, I’m afraid it’s true (except the “faithful believer” part). As long as Robert Marks plainly labels his creationist web pages as unendorsed by Baylor, as long as his remarks are plainly associated with his personal views, not the university’s, they ought to be tolerated. And laughed at, but that goes without saying. That’s the price of academic freedom, that we have to allow the free expression of ideas that we don’t like.

I also sympathize a little bit with Baylor. They’ve got this persistent, obnoxious leech named Dembski who keeps trying to cling to the university, and I can understand how they might get a little overzealous in trying to excise him. It looks to me like they have gotten carried away, though.

Of course, I also experience a little inappropriate glee at the situation. What’s the lesson universities are going to learn from this? If you hire a creationist, you hire a lawsuit-happy twit who is going to embarrass you repeatedly and is going to get crazy crackpot lunacy associated with your academic mission. It doesn’t matter how good he is at his specific discipline, the creationism is going to poison everything.

For another example of embarrassing associations, remember Dembski’s ‘notpology’ to Baylor? Throw away any pretense of apology, Bill. His latest entry was a link to a hideous parody site by one Galapagos Finch (the site seems to consist only of very bad Photoshop jobs where faces are distorted into ugly unrecognizability) expressing resentment that poor Robert Marks was being martyred. That one was very quickly ripped down and tossed into the UD memory hole, but you can still find it preserved in its shameful putrescence at At the Bathroom Wall.

I’m sure hiring committees around the country will take notice of the Dembski style of collegiality.

Evo-devo of mammalian molars

Blogging on Peer-Reviewed Research

I’ve written a long introduction to the work I’m about to describe, but here’s the short summary: the parts of organisms are interlinked by what has historically been called laws of correlation, which are basically sets of rules that define the relationship between different characters. An individual attribute is not independent of all others: vary one feature, and as Darwin said, “other modifications, often of the most unexpected nature, will ensue”.

Now here’s a beautiful example: the regulation of the growth of mammalian molars. Teeth have long been a useful tool in systematics—especially in mammals, they are diverse, they have important functional roles, and they preserve well. They also show distinct morphological patterns, with incisors, canines, premolars, and molars arranged along the jaw, and species-specific variations within each of those tooth types. Here, for example, is the lower jaw of a fox. Look at the different kinds of teeth, and in particular, look at the differences within just the molars.

i-a5e17fbf862bbaf85cb8caf7d8e447d1-fox_jaw.gif
This example — the lower teeth of a grey fox — shows the three-molar dental phenotype typical of placentals.

Note that in this animal, there are three molars (the usual number for most mammals, although there are exceptions), and that the frontmost molar, M1, is the largest, M2 is the second largest, and M3, the backmost molar, is the smallest. This won’t always be the case! Some mammals have a larger M3, and others may have three molars of roughly equal size. What rules regulate the relative size of the various molars, and are there any consistent rules that operate across different species?

To answer those questions, we need to look at how the molars develop, which is exactly what Kavanagh et al. have done.

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Student Report: Fatigue in running

Hello again! It’s been a little while since my last post and I need to post for this week or I’ll be docked points from Dr. Myers. I’ve been a little bit behind on things as I’ve been preparing for my upcoming senior seminar, but I did have time to check out at least one cool article I found on different energy systems used while running.

I had a race today and I noticed that every time I do an 8k (5 miles), about three miles in I hit a wall of fatigue. I get dizzy, it’s hard to focus on the guy in front of me, driving my knee up feels next to impossible, and the only thing I care about is eventually getting to the finish line. I know that much of this is probably because I’ve depleted a good portion of my glycogen stores and have worn out my muscles fairly well. But how does this tie in with my nervous system?

According to the article, a good portion of my glycogen stores are found in my liver. If too much of the glycogen is used hypoglycaemia can occur resulting in brain damage. Other bodily harm such as myocardial ischaemia, heat stroke, and severe ATP depletion from my muscles can occur too if my body is allowed to be pushed far enough.

Luckily for me, my muscles have a built in negative feedback to stop me from killing myself out there. My muscles somehow know to send a signal up to the brain for a release of serotonin and inhibition of dopamine secretion, which results in a further lack of ability to move, which results in a slower time, which puts Morris on the backburner in terms of our men’s cross country team. I’m still wondering though, how do my muscles know when to signal my brain to cut back on the neurotransmitters? And how much does mentality (a positive attitude towards the race, or the expectation of a good run) play a role in the regulation of my muscles (do I release more ACh and endorphins by simply having a good attitude, or is the causality the other way around?)? Either way, if you haven’t moved in a while, get out and enjoy this great October weather while it lasts. Or you can check out this pretty funny link of a band I found on youtube.

Spandrels!

John Dennehy’s citation classic this week is The Spandrels of San Marco and the Panglossian Paradigm: A Critique of the Adaptationist Programme, by Gould and Lewontin. It’s one of my favorite papers of all time — if you haven’t read it, you should do so now. It contains a set of ideas that are essential to understanding evo-devo.

Gould always struck me as a closet developmental biologist — he should have studied it more!

Demons, angels…and now saints

A certain evil old (and now deceased) affliction on the world is being considered for canonization, and they’re tallying up miracles, an absurd activity in itself. One of the “miracles” they’re weighing is that of a man whose kidney stone cleared up after visiting a children’s home founded by Mother Teresa…an awfully tenuous connection, if you ask me, and a rather trivial event. Time magazine starts to agree:

At first glance the elimination of a mineral deposit may seem too insignificant to merit sainthood.

But then of course they go on to make excuses for it. They should have stopped there.

It is insignificant. The connection is thin. The whole premise of sainthood is supernatural silliness. It’s just one big charade.

Consider St. Antonio de Sant’Anna Galvao, whom Pope Benedict XVI canonized last December. Galvao, who died in 1822 (he was on the slow track) was a Franciscan monk in Sao Paolo who distributed “pills” that were actually folded bits of rice paper bearing the prayer: “After birth, the Virgin remained intact. Mother of God, intercede on our behalf.” Believers swallowed them for various ailments. After Galvao’s death nuns in his monastery took up the pill production. According to England’s Daily Telegraph, as his cause for sainthood began picking up steam, they were up to 10,000 pills a day. The Telegraph reported that the local hierarchy opposed the practice, and a senior archbishop commented that it “foster[s] suspicion.” However, the Vatican was apparently satisfied.

Laugh long and hard at the Catholic church. They have a process for posthumously rewarding charlatans for successful chicanery.