The dinosaur lineage that evolved into birds shrank in body size continuously for 50 million years. From left to right are: the ancestral neotheropod (~220 Million years old), the ancestral tetanuran (~200 million years old), the ancestral coelurosaur (~175 million years old), the ancestral paravian (~165 million years old), and Archaeopteryx (150 million years old). Leer más.

Gartersnakes eat newts. I mentioned this remarkable fact in my article on the Scientific American Guest Blog, but it’s interesting enough to warrant a more detailed treatment. In 1990, Edmund D. Brodie III and his father, Edmund D. Brodie Jr, published a paper in the journal Evolution that provided the first evidence of a pair of species in a highly coupled arms race. Leer más.