Evolutionary Biology

One of the events organized for Bora's visit to London was a fantastic behind-the-scenes tour of the Darwin Centre, a newly built section of the Natural History Museum which houses the museum's researchers and contains a vast collection of around 70 million bottled animal specimens. The Darwin Centre's tank room is a most remarkable place. This is where the largest specimens are stored, in glass jars and metal containers whose lids are opened and closed with a system of chains and pulleys suspended from the ceiling. The tank room mostly contains fish specimens, including a coelacanth, but…
Recently published research shows that individual humans will be nicer (more altruistic) when there is the possibility that the recipient of an act can respond verbally. The paper, "Anticipated verbal feedback induces altruistic behavior" is published in Evolution and Human Behavior for March. These results are not particularly surprising, but it is important to confirm these things through experimental work. From the abstract: [Humans may be...] motivated by concerns for praise and blame. ... we experimentally investigate the impact of anticipated verbal feedback on altruistic behavior…
Do you know what the Monty Hall effect is? Let me explain. OK, I'm Monty Hall and you are a hapless game show guest. I show you three doors and tell you that behind one door is a nice brand new car, and behind each of the other two doors is a goat. You get to pick one of the door. Say you pick Door Number 1. Now, I have my lovely assistant Gwenda (assume her name is Gwenda) open Door Number 3 to show you that there is a goat behind Door # 3. I give you the option: Are you going to stick with Door Number 1, or are you going to switch to the only remaining unopened door?…
Grrrrrrrrrrrrr.... Welcome to the Lucky 13th Edition of The Boneyard ... the Web Carnival about Bones and Stuff. "The Boneyard is a blog carnival covering all things paleo, from dinosaurs to pollen to hominids and everywhere in between. It's held every two weeks (the 1st and 3rd Saturday of the month), traveling around to a different blog for each installment, connecting some of the best blogging on ancient life." The previous edition of The Boneyard is here, at Dragon's Tales. The next edition of The Boneyard will be Here at Archaeozoology. If you would like to submit an entry to the next…
I have had this experience. I've traveled literally hundreds of kilometers by foot together with Efe (Pygmy) hunters in the Ituri Forest. We see very few animals. The few we do see are attacked, killed, and eaten. Well, a lot of them actually get away, but that is the idea. But I've also traveled many kilometers (not as many) alone. I would see many animals, and yes, they would run (or climb or whatever) away, but not as desperately. They knew I was not really one of the hunters, although I tried my best to look tough and hungry. Of course, when I use the word "animal" here I mean…
A very important and truly wonderful paper in Nature described a tour-de-force analysis of the Mammalian Evolutionary Record, and draws the following two important conclusions: The diversification of the major groups of mammals occurred millions of years prior to the KT boundary event; and The further diversification of these groups into the modern pattern of mammalian diversity occurred millions of years later than the KT boundary event. The KT boundary event is the moment in time when a ca. 10 km. diameter object going very fast hit the earth in the vicinity of the modern Yucatan, causing…
... well, OK, maybe that is a slight exaggeration. You know about giardia. Giardia intestinalis. It causes a nasty gut infection, and you get it by drinking water pretty much anywhere in the US (potentially). It is very hard to get rid of. Giardia adapt to immune system attacks (of their host) in a way that passes that adaptation down to their offspring without genes. It is a Lamarkian process. Giardia have no mitochondria, yet many of the genes known to be in mitochondria in eukaryotes are found in the giardian nucleus. So, ancestral giardia probably had mitochondria, but all those…
Syphilis is first clearly seen in Europe in 1495, when it appeared as a plague (though it was not "the blague" ... Yersinia pestis) among Charles VIII's troops. When these troops went home shortly after the fall of Naples, they brought this disease with them, staring an epidemic. The level of mortality in Europe was truly devastating. Is it the case that syphilis was brought to Europe by Columbus and his men just prior to the plague-like outbreak of 1495? The origin of syphilis has been debated for years, really since the actual 1495 event itself. Some researchers have asserted that…
How do you avoid having sex with your close relatives? Well, not you, specifically, but how is it done generally, or perhaps among mammals in particular? One obvious way would be to use a part of the genome that seems to evolve rapidly, and that would be able to distinguish between even moderately closely related individuals. For instance, the Major Histocompatibility Complex (MHC) is big, diverse, and changes rapidly. If two potential mates could somehow compare their MHC's, they could estimate their degree of relatedness, and thus avoid inbreeding. An article just out in Current Biology…
The question is basic: Is evolutionary change largely random or is it more often shaped by selective forces? The former is linked to what is called Neutral Theory, and it has a lot of support, to the extent that it most likely true. The latter is part of what is sometimes known as the Adaptationist Program, and it is certainly correct. New research on the Development of the Nematode Vulva is sure to cloud the issue even further.. First, a word on this confusing introduction. We know that when we observe life, we do not see a really wide range of degree of adaptation among closely related…
The ape human split is a bit of a moving target. In the 1970s and early 1980s, there were geneticists who placed it at very recent (close to 4 million years ago) and palaeoanthropologists, using fossils, who placed it at much earlier. During the 1980s, the ape-human split moved back in time because of the importance of sivapithecus, then later in time when Sivapithecus slipped and fell out of the hominid/hominin (human ancestor) family tree. Meanwhile the geneticists were moving towards a more and more recent split. At one point not too long ago, all the evidence converged with the split…
Welcome to Berry Go Round #3, the blog carnival deicated to all things botanical. The previous installment, Berry Go Round #2, is located here, at Further Thoughts. If you would like to submit an item to the next Berry Go Round, you may use this handy submission form. The Berry Go Round Home Page is here. Let us begin right away with the Artichokes. Seeds Aside has a piece on the relationship between the artichoke and the cardoon, both known in ADL (ancient dead language) as Cynara cardunculus. The phyloge relatinship between the two, and the story of domestication for each, is very…
A comparative neuroimaging study performed by researchers from Emory University in Atlanta, Georgia, in collaboration with colleagues from the University of Oxford, provides clues to how human language evolved. In the past, it was believed that the increase in brain size during human evolution occured mainly to accomodate our complex linguistic abilities. But the findings of this new study suggest that the emergence of language also required major modifications in how the brain is wired. Using diffusion tensor imaging (DTI, a type of functional magnetic resonance imaging which I described in…
Myers? Myers? .... Myers? ..... Myers? (He's not here, Ben ... Your producer threw him out.)You know about the incredibly ironic dust up, whereby Expelled! producers kicked PZ myers out of line at a pre-release showing, but failed to notice that Richard Dawkins was standing right next to him. The evidence suggests that this major bit of bad publicity for Expelled! may have led to the movie being pulled from some pre-release showings. It it too early to be sure of this, and there may be several factors other than the utter embarrassment of this incident at play here. For instance, it is…
A common presumption is that behavior is part of phenotype, and since phenotype arises from genotype (plus/minus Reaction Norm), that there can be a study of "behavioral genetics." This is certainly an overstatement (or oversimplification) for organisms with extensive and/or complex neural systems, such as humans and mice. Neural systems probably evolved (not initially, but eventually) to disassociate behavior with the kind of pre-determined micro-management of behavior that a simple gene-behavior link requires. However, in organisms with neural systems the size of the period at the end of…