Evolution

“It is demonstrable,” said he, “that things cannot be otherwise than as they are; for as all things have been created for some end, they must necessarily be created for the best end. Observe, for instance, the nose is formed for spectacles, therefore we wear spectacles. The legs are visibly designed for stockings, accordingly we wear stockings.” - Candide by Voltaire Humans are unique among the great apes (of which we are one) in various ways. One of them is our possession of a very long Achilles tendon, which is quite short in chimpanzees, gorillas, and orangutans. Most anthropologists…

A recent article titled ‘Protective buttressing of the human fist and the evolution of human hands’ rests on the assumption that human evolution has been characterised by competition for mates, however despite modern human’s propensity for violence and competition, it is an assumption that should not be taken for granted.  A recent study by Michael H. Morgan and David R. Carrier titled ‘Protective buttressing of the human fist and the evolution of human hands’ makes clear that the human hand has unique proportions that allow it to be used effectively as a fist. They suggest this is no…

This past May, I was fortunate enough to take part in a conference in Venice, Italy, which was a retrospective on the legacy of famous paleontologist and author Stephen Jay Gould 10 years after his death. The choice of Venice as the conference venue was a nod to one of Gould’s most famous and influential papers, “The Spandrels of San Marco and the Panglossian Paradigm: A Critique of the Adaptationist Programme“, which he co-authored with Richard Lewontin in 1979. In the paper, Gould and Lewontin (1979) drew an analogy between the “spandrels” (or, if you’re overly pedantic about architectural…

Neil Shubin alert: Researchers have found evidence that the development of hands and feet occurred through the gain of new DNA elements that activate particular genes - and they used a zebrafish to show it.  The transition from water to land was obviously a major event in the history of vertebrate life. In order to understand how fins may have evolved into limbs, researchers introduced extra Hoxd13, a gene known to play a role in distinguishing body parts, at the tip of a zebrafish embryo's fin. This led to the generation of new cartilage tissue and the reduction of fin tissue—…

Human hands and their remarkable dexterity have given us everything from the guitar of Segovia to the art of the Dutch masters but, says David Carrier from the University of Utah, they evolved to be what they are for a more practical reason.  As a weapon.  Carrier and colleague Michael Morgan publish their hypothesis that human hands evolved their square palms and long thumb to stabilise the fist and produce a compact club for use in combat in The Journal of Experimental Biology. Carrier says the idea occurred to him during an impassioned discussion with fellow biomechanic Frank…

Bacteria have lived for millions of years in our planet where, with an impressive capability to adapt, they now colonize virtually every environment, including us. But as tiny one-cell organisms they had to learn to work together to be powerful enough to act on the environment and other organisms. And now, new research has discovered that their evolution is triggered exactly by these interactions, as scientists from Centre for Environmental Biology at the University of Lisbon in Portugal and the Institute Pasteur in Paris show that bacteria’s genes for secreted proteins - the ones that…

From an evolutionary standpoint, homosexuality is a trait that should not develop and persist in the face of natural selection. Yet it exists in most cultures, among men and women. Analyses have noted that homosexuality can run in families, leading researchers to hypothesize a genetic underpinning of sexual preference but no gene or group of genes for homosexuality have been found, despite numerous studies searching for a genetic connection.  That may be because homosexuality is epigenetic, rather than genetic, according to a new model.  Epigenetic tags, a cell's epigenetic profile…

Neuroscientists think they have some insight for evolutionary biologists into how humans, and other mammals, have evolved to have intelligence. They say they have identified the moment in history when the genes that enabled us to think and reason evolved. This point 500 million years ago provided our ability to learn complex skills, analyze situations and have flexibility in the way in which we think, says Professor Seth Grant of the University of Edinburgh, who led the research -  "One of the greatest scientific problems is to explain how intelligence and complex behaviours arose during…

What happens when the modern evolutionary theory of punctuated equilibrium collides with the older theory of mosaic evolution? That's the issue addressed by paleobiologists Melanie J Hopkins at the Museum fuer Naturkunde Berlin and Scott Lidgard at the Field Museum in Chicago.   While processes of evolution are largely studied by observation and experiment in the living world, evolutionary tempo and mode – rates and patterns of change, respectively – are mostly revealed by studying the fossil record. Paleontologists measure parts of the hard skeletal fossil remains of once-living…

Genetic blending between Europeans and Asians occurred over 2,000 years ago in the Altai region of Mongolia, according to a new analysis.  The remains of ancient Scythian warriors indicate that this blending was not due to an eastward migration of Europeans, but to a demographic expansion of local Central Asian populations and that was due to the technological improvements the Scythian culture brought with them.  The Scythians were an Indo-European people dedicated to nomadic pasturing and horse breeding. They crossed the Eurasian steppes from the Caspian Sea until reaching the…