Tag Archives: thyroid hormone

Tom Nelson interview with me about the failed polar bear narrative and rapid evolution

You can watch my interview with Tom Nelson about the latest issues in polar bear conservation and highlights of my latest book, Polar Bear Evolution.

On Youtube:

Tom tells me, “It’s also up on other video sites such as Rumble and BitChute, and will soon be available on other podcast apps such as Apple Podcasts (most, but not all, of those are audio-only).  It should also be on Spotify, Google Podcasts, Pocket Casts, Podvine, Overcast, Amazon Music podcasts, Audible podcasts, Castbox, RadioPublic, Twitter, etc.”

Summary: Susan Crockford, a zoologist, discusses the challenges in accurately estimating polar bear populations and the ongoing debate between Inuit communities and polar bear specialists regarding population sizes. She also shares her theory on the role of thyroid hormones in polar bear evolution and the quick adaptation of species to new environments using the example of the Russian foxes.

A list of topics covered, by time-stamp in the interview, is listed below.

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The story of polar bear evolution could not be told without discussing climate change

Polar bears arose as a new species because the climate changed and forced some brown bears to colonize the sea ice. Polar bears epitomize the story of how evolution works but perhaps not quite how you imagined it.

Moving from extremes in warmth to extremes in cold characterized the last million years of geological history, as the graph above shows, where odd-numbered Marine Isotope Stages (MIS) are warm interglacials and even-numbered stages along the bottom are cold glacials. MIS 2 was the Last Glacial Maximum.

But where and when during this period of change did polar bears come to be–and how, exactly, did it happen? My new book tells the whole story, which has never been done before. Not long to wait now, the release date is only about a week away (1st week June).

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Podcast with WildFed about polar bears and domestication as speciation

A couple weeks ago I had a fabulous chat with Daniel Vitalis from Wildfed about a wide range of topics, including my work on polar bears and domestication as a process of speciation. The podcast went live this morning – have a listen here (also copied below), I think you’ll enjoy it. One hour, 36 minutes.