Duck-billed dinosaurs have puzzled paleontologists for years, particularly because certain chambers in some of their skulls did not seem to have a clear purpose. But CT-scanning, originally designed for medical use, seems to support scientific speculation that the chambers played some role in communication between the animals.

Many have experienced the calming effects that a simple stroll in a park can produce, but scientists are discovering that walking in green surroundings can also reduce the symptoms experienced by children diagnosed with attention deficit hyperactivity disorder (ADHD).

In a recent issue of the journal BioScience, ecologist Jeffrey Levinton of Stony Brook University, New York, offered a well-written review of the current status of the “Cambrian Explosion” hypothesis and presented at least two enigmas in evolutionary thinking.¹

On October 7, 2008, University College London professor and geneticist Steve Jones delivered a bold lecture entitled “Human evolution is over.”¹ In the past, he stated, elderly fathers provided more mutations for evolution to work with. Now that men are becoming fathers at younger ages, humans are not evolving much at all.

Biologists are having a difficult time figuring out how to fit a tropical fish’s rapid coloration changes into the story of evolution. A new study examined the role these changes play in the fish’s mating habits, and concluded that they could contribute to the development of different species.