UPDATE AND EVOLUTIONARY LESSON: We have a winner! I thought this would go fast. Palefury, comment #16, guessed correctly: giant panda (top), grizzly bear (middle) and polar bear (bottom).
Note how well the teeth suit the animal’s diet. Pandas are herbivorous, nomming the stems and leaves of bamboo, and need tough teeth for grinding. To do this, their teeth evolved a broad, flat shape. Grizzlies are omnivores: they have “Swiss Army teeth,” useful for eating both vegetation and meat (note the higher cusps that aid in shearing flesh). Finally, polar bears are completely carnivorous, and their teeth are “carnassial,” with high cusps for shearing the flesh of seals. These animals are all in the family Ursidae.
I still feel bad that nobody guessed the winner of this year’s Nobel Prize for Medicine/Physiology. Therefore, I’m putting up the spare autographed copy of WEIT to the person who correctly guesses the identity of the three mandibles (lower jaws) shown below. I took this photo during my visit to Kentucky. They’re from three different species in a single family of mammals. Name the species (giving both the scientific and common names) in order from top to bottom, and explain how you identified these. Click to enlarge the photos. (Ignore the mandible nestled inside the middle one.)
First correct winner gets the book; contest closes at 4 pm tomorrow or when there’s a winner—which there will be. Employees or students of the University of Kentucky, and their relatives, are ineligible.
The answer will appear in this space.