A New York Medical College developmental biologist whose life’s work has supported the theory of evolution has developed a concept that dramatically alters one of its basic assumptions—that survival is based on a change’s functional advantage if it is to persist. Stuart A. Newman, Ph.D., professor of cell biology and anatomy, offers an alternative model…
Palaeogeneticists have examined 158 DNA-containing leg bones belonging to three species of extinct giant birds called moa. The bones, which were between 600 and 8,000 years old, had been recovered from three sites within 5 kilometres of each other. By comparing the specimens’ ages and degrees of DNA degradation, the researchers calculated that DNA has…
From SciAm guest blogger Kyle Hill: The Earth is flat. A full moon leads to more crime. Humans were created less than 10,000 years ago. If you made your way through even the most general of science educations, the above statements should strike you as suspect. Having a Copernican worldview challenged by such a statement,…
John B. Gurdon of the U.K. and Shinya Yamanaka of Japan shared this year’s Nobel Prize in Physiology or Medicine for their work in so-called cellular reprogramming, which has unleashed a wave of advances in everything from cloning to the possible treatment of diseases using stem cells. The researchers’ experiments showed how specialized, mature cells…
A new study suggests that present-day Europeans share more genes with now-extinct Neandertals than do living Africans, at least partly because of interbreeding that took place between 37,000 and 86,000 years ago. Cross-species mating occurred when Stone Age humans left Africa and encountered Neandertals, or possibly a close Neandertal relative, upon reaching the Middle East…
Washington State University researchers have found that the great-grandchildren of pregnant rats exposed to low doses of dioxin develop diseases and reproductive abnormalities — even though they did not have direct exposure. The finding challenges the traditional explanation of how traits are passed from one generation to another.
In certain toy racecar tracks, sneaky players can flip a switch, trapping their opponents’ vehicles in a loop of track. Cells employ a less subtle approach: they change the track’s layout. In a study published online in Science, scientists at the European Molecular Biology Laboratory (EMBL) and Oxford University discovered that, by forming or undoing…
Using an innocuous bacterial virus, bioengineers have created a biological mechanism to send genetic messages from cell to cell. The system greatly increases the complexity and amount of data that can be communicated between cells and could lead to greater control of biological functions within cell communities. The researchers, Monica Ortiz, a doctoral candidate in…
There seems to be little that distinguishes the indigenous Tsimane of northern Bolivia from dozens of other native Amazonian peoples. They still live in small communities, fishing daily, hunting and relying on subsistence farming. They remain relatively isolated from the outside world. They still have large families and fall victim to parasites, worms and infectious…
Chimps may be similar to us in many ways but they can’t compete when it comes to brain size. Now for the first time we can see when the differences emerge by tracking the brain development of unborn chimps. Researchers in Japan subjected a pregnant chimp to a 3D ultrasound to gather images of the…