Julia Evangelou Strait

Julia Evangelou Strait
Peter Raven
St. Louis Public Radio file photo

Once every three months, Peter Raven pays a visit to his dermatologist. Summers spent at 10,000 feet, hiking northern California's Sierra Nevada Mountains and roaming the sand dunes and vacant lots of San Francisco take their toll. "That did a real number on my skin. Of course, nobody thought a thing about the sun in the 1950s," Raven said, describing a boyhood spent outdoors, rearing butterflies, collecting insects and gathering plants.  

An international team of scientists has sequenced the genome of a duck-billed platypus. Part bird, part reptile and part mammal, the platypus genome sheds light on the evolution of mammals, including humans, and on the genetics of disease. Led by Richard K. Wilson, director of the Genome Sequencing Center at Washington University School of Medicine, the scientific team found that this mammal's DNA is as unusual as its duck-bill.

Mixed-up Mammal