PORT TOWNSEND — Liz Nesbitt will tell of the end of the Cretaceous time period, when dinosaurs became extinct and mammals began to flourish, at Quimper Unitarian Universalist Fellowship, at 4 p.m. Saturday.
The hourlong lecture at 2333 San Juan Ave. is free and open to the public. Donations of $5 will be accepted.
After late-Cretaceous extinctions 66 million years ago, global climates remained warm, and Earth was free of ice sheets, Nesbitt said.
The hothouse climate persisted until about 35 million years ago, when the world was plunged into icehouse conditions and ice sheets spread across the high latitudes for the first time in 200 million years.
With extinction of all large dinosaurs and marine reptiles, mammals rapidly evolved to fill many vacated ecological niches.
Nesbitt is the curator of paleontology at the Burke Museum in Seattle and is an earth sciences professor at the University of Washington.
Much of Nesbitt’s research involves the effects of changing climate on marine faunas, from large vertebrates to invertebrates and microscopic forms.
She is working with Burke colleagues on measuring the health of Puget Sound through examination of foraminifera in bottom sediments.
For more information, visit www.quimpergeology.org.
