In this class, Dr. Keislar begins a major topic: Different types of intelligent life in our galaxy and universe. First telling about friendly reptilian species he (and leading science fiction writer Arthur C. Clarke) have met, he goes on to mention many other species. Interestingly, apart from human and very human-like beings (similar to primates) there exist intelligent humanoid species resembling many forms of animal life that we are familiar with, including not only reptiles, but mammals like horses, cats, dogs, cetaceans (whales and dolphins, which are themselves intelligent species), amphibians like frogs, birds, and even insects like grasshoppers and praying mantises.
It was astonishing to the Secret Space Program scientists who encountered them that these intelligent life forms almost all are humanoid, that is, they stand upright and have a head with (usually) two eyes, two ears and a nose with nostrils (though these may be only slits), and a torso with (usually) two arms and two legs – though not infrequently with a tail, and even sometimes wings or horns. There are also, however, intelligent life forms with bodies shaped like a sphere.