If that title doesn't get hits, nothing will.

In celebration of President's Day (which I have off work), Valentine's Day (which I do not have off work), and Charles Darwin's birthday (which isn't even a holiday), Olivia Judson has written a brilliant article on the mating habits and physiology of Tyrannosaurus rex at her New York Times blog, The Wild Side.

Now if we stipulate that:

1. All little boys love dinosaurs.
   • T. rex is the coolest dinosaur.

   • Some little girls love dinosaurs too.
2. All big boys love sex.
   • Again, some big girls too (probably a great many more than loved dinosaurs when they were little).

   • Okay, I think we can agree that everybody loves sex.

We clearly see that Judson's choice of topic was well-calculated genius. Distilled by this genius is a terribly interesting look at both the evolutionary biology and natural history of dinosaurs and their closest living relatives...

So what can we say about dinosaurs? My guess is that the males had members — but it’s an educated guess. It’s based on an analysis of dinosaur relations.

Two living groups are most closely related to dinosaurs. One is the crocodiles. Male crocodiles have a penis — just one — which, most of the time, they keep tucked inside their cloacae. (In most species of crocodile, it’s hard to determine the sex of living animals without an intimate exam, never mind dead ones.) Compared with the mammalian penis, the crocodile’s has an oddity: sperm is transported along an external groove, rather than through an internal tube.

The other group related to dinosaurs is the birds. Indeed, to be strict about it, birds are dinosaurs. If you look at a family tree of dinosaurs, birds, and other reptiles, you see that the lineage that evolved into dinosaurs split off from the lineage that evolved into crocodiles. Birds, in contrast, evolved directly from a dinosaur lineage. Birds are more closely related to T. rex than they are to any living form.

Birds themselves divide into two main groups, formally known as the palaeognathous and the neognathous. The palaeos comprises the big flightless birds such as ostriches, emus, rheas, and cassowaries, as well as kiwis and an obscure (but flying) group of south American birds, the tinamous; the neos covers everything else. The palaeos have penises; like crocodiles, they keep them tucked into their cloacae. Again like crocodiles, the organ has an external groove for sperm. What’s more, the lineage leading to the other endowed birds, the ducks, geese, and swans, appears to have split off from that of the other neos relatively early.

This strongly suggests that the ancestor of all birds had a penis, and that at some point early in the evolution of the neognathous birds, the penis got lost. Since crocodiles have one, and ancestral birds almost certainly did, and since the two groups have such similar genital morphology, I think it’s a safe bet that the lineages between crocodiles and birds — that is, dinosaurs — had one, too.

Now, the next question — what did it look like? Was it large or small? Fancy or plain? I wouldn’t like to guess. The blue-billed duck (Oxyura australis) is just a little fellow — he weighs less than one kilogram (two pounds) — but his penis measures 28.5 centimeters (11 inches), and it’s covered with knobs. In contrast, the mighty ostrich (Struthio camelus), which can weigh as much as 160 kilograms (350 pounds), has a penis that’s a mere 20 centimeters (8 inches) long. But at least it’s bright red.

Happy Valentine's Day.

The Associated Press would have you believe that Harvard is undertaking the unprecedented task of going toe-to-toe with the intelligent design. Obviously some individual scientists have chosen to speak out about the relatively merits of ID versus, well, science, but no research institution that I’m aware of has deigned to compare ID with evolution as part of its agenda. The AP article linked above seems to imply (without directly stating) that Harvard’s new research program is intended to study the merits of the two theories. It does this not only spending almost half the [short] article explaining ID, but also by titling the piece “Harvard Jumps Into Evolution Debate” (emphasis mine).

The thing is, if you look at the substance of the information given about Harvard’s new program, it doesn’t sound at all like it’s intended to look at evolution or intelligent design, but rather at the probable origin of life. Perhaps this doesn’t sound like a major distinction, but it’s important to recognize that evolution is not a theory of origins. Rather, evolution attempts to explain how the organisms born at the origin of life became the organisms on Earth today. The Harvard program discussed in the article appears to be more interested in how those initial organisms arose (hence the name of the program “Origins of Life in the Universe Initiative”).

All the same, I’ve got a hunch that if the scientists involved talk about ID at all, it’ll be while have a few laughs over beers after work.

Evolution and origins are always good topics for troll comments; let’s go fishing.

There’s been a big hubbub this week on the science blogs about Bush’s recent remark suggesting that ‘intelligent design’ ought to be taught in public schools alongside evolution. What caught me most off-guard about the quote is that other people were so shocked by it. I think it’s my zealous following of any news regarding climate change that has made me so jaded about this administration’s willingness to utterly ignore scientific evidence, even widely acknowledged facts, in favor of political pressure, religious fundamentalism, or good old money.

From a policy perspective I’m not even convinced yet that this is as big of a deal as Bush’s willful ignorance of climate change. Hear me out.

My rudimentary understanding of education policy is that curricula requirements are developed primarily at a state level. I think a major part of this perception is due to the recent state-level controversy about the teaching of ‘intelligent design’ in Kansas. Conversely, Bush has the power to abrogate any international treaty that Congress deigns to make regarding restrictions to carbon emissions specifically or climate change in general.

If I’m right, then while Bush’s opinion about ID is an unpleasant reminder of the current administration’s ideology, it has little weight as far as the direction of education policy in America, especially in light of the fact that Bush’s belief puts him at odds with his own science advisor:

None of the coverage that I could find, however, made a very simple contrast between Bush's remark and prior statements on "intelligent design" by presidential science adviser John Marburger. As I have previously reported, Marburger told a group of science reporters earlier this year that "Intelligent Design is not a scientific theory." Thus, my follow-up question to Bush would have been, "Mr. President, are you aware that your very own science adviser says 'intelligent design' doesn’t qualify as science? Don't you consult with him about these things?"

Anyway, for better informed commentary than mine, as well as a list of the multitudinous other blogs that have dealt with this issue, check out PZ’s coverage at Pharyngula.

I’m sure everyone has had enough of the doom and gloom over the retirement of Sanda Day O’Connor, but I can’t help but point to Chris Mooney’s post about the possible ramifications for the teaching of evolution in public schools. Check it out.

Given today's news, I'm sure we could all use something to laugh about. Enter Family Guy:

Via Stranger Fruit.

Two articles on evolution in one evening? What is this, frickin’ Pharyngula? Anyway, the Economist has an interesting piece up on the possibility that selective pressure is responsible for a biological difference in intelligence between Ashkenazi Jews and, well, everyone else. Gregory Cochran, the author of the paper, is no stranger to controversy, having previously suggested that homosexuality is the product of an infection. I’m not touching that with a ten-foot-pole (though any curious reader who looks into it is encouraged to post a comment with more info), but his thesis on intelligence among Ashkenazim seems to be worth considering.

Essentially he’s suggesting that the set of genes that causes diseases such as Tay-Sachs, Gaucher's and Niemann-Pick – all of which strike Ashkenazi Jews more frequently than most other people – are also responsible for heightened intelligence. This is where Cochran still has some evidence to collect – he doesn’t yet have proof that the same allele is responsible for the genetic disorders as well as heightened intelligence. At the same time, Cochran’s proposal sounds strikingly like an interaction that we already know to be real: sickle cell anemia and malaria.

West Africans, and people of West African descent, are susceptible to a disease called sickle-cell anaemia that is virtually unknown elsewhere. The anaemia develops in those whose red blood cells contain a particular type of haemoglobin, the protein that carries oxygen. But the disease occurs only in those who have two copies of the gene for the disease-causing haemoglobin (one copy from each parent). Those who have only one copy have no symptoms. They are, however, protected against malaria, one of the biggest killers in that part of the world. Thus, the theory goes, the pressure to keep the sickle-cell gene in the population because of its malaria-protective effects balances the pressure to drive it out because of its anaemia-causing effects. It therefore persists without becoming ubiquitous.

The article goes on to explain Cochran’s historical argument for how the disease/intelligence genes might have been selected for among Ashkenazim. I wonder though, how strong of a selective pressure the conditions he discusses could actually exert on intelligence. We know that rapid evolution can occur in the face of very strong selective pressures (see ex. antibiotic resistant bacteria or pesticide resistance development among insects), but I don’t see Cochran’s proposed pressures as especially “strong,” especially in light of the relatively short period of time in question (1,200 years or so for a species with ~25 year generations = ~50 generations). Will the kooky Darwinists in the room please stand up and tell me whether I'm full of it or not?

Oh, and if you’d like to read the paper for yourself (I confess that I only skimmed parts of it) you can check it out here (PDF).

Remember back in March when Mary Schweitzer found soft tissue inside a T. Rex bone? Back then I said that “the discovery could shed light on […] the evolutionary relationship between dinosaurs and contemporary species.” Am I a freakin’ prophet or what?

Today we learn that the unusual gross anatomy from the interior of the MOR 1125 femur was immediately recognized by Schweitzer as Medullary bone. Medullary tissue is a calcium-rich layer lining the inside of bird’s bone marrow cavities that develops during the egg-laying process. The formation of medullary tissue is today uniquely avian and distinct from reptilian egg-laying biology.

The tissue in question is also an indicator as to the gender of the specimen – since medullary tissue is created only my momma dinosaurs, any specimen that’s missing it is either male or under age. Keep your eyes open for a more detailed analysis at the Panda’s Thumb once they’ve had a chance to sift through Schweitzer et al.’s paper.

A growing peeve of mine lately, which I attribute to rubbing off from Christine (soon to be doctor of Biological Anthropology), has been how mainstream media and even publications with a more science/technical readership (like Wired) make blatantly wrong statements about Darwinism/evolution in relation to the religious right's attempts to have schools teach "Intelligent Design" as part of its larger "moral" crusade of telling Americans what they can and can not do/think. (Yes, I am the king of run on sentences) In contrast there is a great article in the latest New Yorker about "Intelligent Design" that everyone should check out. It does a good job going over just exactly what the "science" behind the political movement is and makes well informed responses to them.

I seem to have hit a nerve with the pop quiz on evolution I posted earlier this week, so here’s another fun tidbit on evolution:

This article exemplifies so much of what is wrong with public discourse about science. PZ Myers has posted a nice jumping-off point for those interested in more detailed information about the facts of the case, but the gist is that the Kansas Board of Education has called hearings over whether to adopt new science standards that would require the teaching of alternative theories to evolution.

I’m not writing this to address the details of the “debate” over evolutionary theory, but rather to examine the language used by the author in her coverage of the Kansas hearings. Specifically, I have a major problem with the author’s insistence on referring to evolutionary theory as “Darwinism.” Effectively she’s creating a straw man by resting evolutionary theory entirely on the shoulders of our long dead friend Charles Darwin rather than giving it its proper credence as one of the most developed fields of modern biology.

I don’t think this is malicious intent on the part of the author, but rather a remarkable success on the part of denialists. They are managing to twist the popular rhetoric to make the debate about a person who can easily be defamed rather than a theory that is supported by scientific evidence and will require additional actual evidence to alter or deny.

The always exceptional Pharyngula points us to the National Center for Science Education’s responses to Dr. Jonathan Wells’ “Ten Questions to Ask Your Biology Teacher.” None of Wells’ critiques are new, but the NCSE’s responses are pointed and concise, and deserve the widest distribution possible. As such, they are pasted below the fold.