Pegging, defined by Dan Savage as the sexual practice in which a woman penetrates a man's anus with a strap-on dildo, is taboo. It's an eventuality surrounded by incredulity. Many gay men look suspiciously -or with hope- at straight men who like to be penetrated.
What two characteristics make mammals unique from other vertebrates? Mammals are unlike other vertebrates in two distinct ways. First,  all mammals have hair, unlike other vertebrates. Also, female  mammals carry their offspring to full term â¦in the uterus, whereas  most other vertebrates lay eggs.
Accurate Classification [edit]. Often organisms are hard to classify. For example, the duck-billed platypus is homeothermic, has lungs and provides milk for the young. These are the classic features of mammals, yet the platypus also is oviparous.This is not a feature of mammals, as mammals are the only viviparous class of animal.ccurate Classification [edit]. Often organisms are hard to classify. For example, the duck-billed platypus is homeothermic, has lungs and provides milk for the young. These are the classic features of mammals, yet the platypus also is oviparous.