From Maxwell’s dogs and Hubble’s cat to Tycho Brahe’s unfortunate elk, four-legged friends have been a mainstay in lives of great scientists.

Here’s a look at influential scientists whose pets gave them paws for reflection.

Watch a Perimeter Institute talk on Einstein and his (two-legged) collaborators.

Read Tesla’s letter to a friend about his early fascination with electricity.

Read the evidence for (and against) Newton’s invention of the cat door.

Check out the Slice of PI on the life and work of Edwin Hubble.

Check out the Slice of PI on Richard Feynman’s most notable quotes.

Watch “Boltzmann’s Dog and Darwin’s Finch,” a biophysics colloquium at Perimeter Institute.

Watch a short documentary about the life and work of James Clerk Maxwell.

Learn more about the astronomical work and odd life of Tycho Brahe.

Find out more about Burschie and all of Schrödinger’s animals in this PBS Nova article “Schrödinger’s Menagerie”.

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