Nearly 3,000 people cast their vote during our first round of March Mammal Madness, narrowing the possible names for our hypothetical common placental ancestor down to 16. Help us narrow down the choices even further by voting for your favorites below. You have until 5 pm EDT on Tuesday, March 19, to make your selections.

The “Name Your Ancestor” contest resulted in more than 1,000 name suggestions for the hypothetical common placental ancestor that scientists described last month. The top 32 contestants, as selected by the Museum and WNYC’s Radiolab, range from serious to silly. Starting today, we need your help to pick the winning moniker for this small, furry, insect-eating mammal. 

Most of us know about blue whales, sperm whales, and dolphins (a type of specialized whale). But what about beaked whales, an elusive group that includes nearly a quarter of all living whale species? 

Like hippos, their closest living relatives, whales are descended from an ancestor that had four legs and walked on land, a transition explored in the upcoming exhibition Whales: Giants of the Deep, opening March 23.

This month, a team of international researchers led by the American Museum of Natural History and Stony Brook University determined in unprecedented detail what the earliest ancestor of placental mammals—the widely diverse group of animals ranging from whales to bats to humans—looked like.  The Museum is teaming up with WNYC’s Radiolab to sponsor a tournament to name this early ancestor. Want to enter?