Evolution

Researchers who make generalizations about the effects of domestication and dog-wolf differences in the utilization of human visual signals, take note; a new study says dog breeds selected to work in visual contact with humans, such as sheep dogs and gun dogs, are better able to comprehend a pointing gesture than those breeds that usually work without direct supervision. In a series of tests, Márta Gácsi from Eötvös University, Hungary worked with a team of researchers to examine the performance of different breeds of dogs in making sense of the human pointing gesture. Gácsi said, "It has…

How evolution can bridge the gap between two discrete physiological states is a question that puzzles biologists and therefore delights critics. Most evolutionary changes happen in tiny increments; an elephant grows a little larger, a giraffe's neck a little longer and if those tiny changes prove advantageous there is a better chance of passing them to the next generation, which might then add its own mutations until you may end up with a huge pachyderm or the stretched neck of a giraffe. But when it comes to traits like the number of wings on an insect or limbs on a primate there is no…

Science is occasionally a life-threatening career choice, particularly for those scientists who risk shipwreck, starvation, disease, and large, arctic carnivores to unlock the mysteries of the life's past. Sean Carroll, in Remarkable Creatures, looks at how the drive to explore, the itch for discovery that pushed Columbus and Magellan on their great voyages, has worked its magic on those great scientists who have pursued scientific adventures to the most extreme corners of the earth. What makes a scientific adventurer tick? Carroll answers this question by taking us through a series of mini…

It's not a secret to you if you have watched football for the last 40 years;  a guy once almost big enough to be a linebacker can't even be a safety today.   Elite athletes are getting bigger. Specifically, while the average human has gained about 1.9 inches in height since 1900, new research showed that the fastest swimmers have grown 4.5 inches and the swiftest runners have grown 6.4 inches. In a new analysis, Jordan Charles, an engineering student who graduated this spring, collected the heights and weights of the fastest swimmers (100 meters) and sprinters (100 meters) for…

Speciation, where different populations of the same species split into separate species, is central to understanding evolution. As would be expected in a complex process like evolution, it's difficult to observe in action.  A new study in American Naturalist says they have captured two populations of monarch flycatcher birds just as they arrive at that 'evolutionary crossroads' of speciation - and it involves a change in a single gene. Monarch flycatchers are small, insect-eating birds common in the Solomon Islands, east of Papua New Guinea. Uy and his team looked at two flycatcher…

Do our genomes look designed? Let's address this point, hoisted from the comments of this post: Actually, shared genetics between chimps and humans is agnostic with respect to evolution or "intelligent design". In software engineering, you often find shared code (or even junk code) in the source of various projects as it develops from "Product 1.0" to "Product 2.0" to "Product 3.0". I.e., it's a strawman argument to assume the "intelligent designer" started from scratch for chimps and humans. That doesn't sound intelligent at all. Like a software designer, the "designer" would have hacked up…

I’ve been prompted to write this because of the misconceptions about the concept of the “Selfish Gene” in Evolutionary theory – evident in both blog replies on this site and more widely. I get really irritated when I see writers in the social sciences characterise evolutionary biology as somehow being based on the same assumptions as rational choice theory. Here is the first paragraph from a book chapter I saw today which motivated me to start this blog and write this entry...Evolutionary Theory and Cooperation in Everyday Life David Sloan Wilson and Daniel Tumminelli O’Brien "Theories of…

Possibly one of my biggest issues with the way evolutionary theory is described in the social sciences today is the characterization of evolutionary biology as somehow being based on the same assumptions as rational choice theory. Here is the first paragraph from a book chapter I saw today which motivated me to write this blog entry... Evolutionary Theory and Cooperation in Everyday Life David Sloan Wilson and Daniel Tumminelli O’Brien "Theories of cooperation in both biology and the human social sciences have had a turbulent history. During the nineteenth and early twentieth centuries, it…

In light of the popularity of this piece, here are some things to keep in mind about 'selfish' genes: 1. The basic issue is about the unit of selection - does natural selection choose allele, individuals, populations, or species? The answer, like most things in biology, is yes, as Douglas Futuyma puts it in his standard textbook on evolution (p. 354. 3rd edition): If, then, our concept of levels of selection includes causality, natural selection can act at the level of the gene (as in meiotic drive), organism, and at least in principle, population and species. In light of the popularity of…

Parasites don't get a lot of respect these days but we may have to reconsider that.  In spite of their nasty reputation, they may have given us the joy of sex. What's so great about sex? If you don't know, this article cannot help and even from an evolutionary perspective the answer is not as obvious as one might think. Despite its central role in biology, sex is something of an evolutionary mystery. Reproducing without sex, like microbes, some plants and even a few reptiles, would seem like a better way to go.   It would save countless nights spent in bars because every individual…