When compared with moms who had difficult deliveries ending in vaginal birth, women in the study who had cesarean deliveries said they had more problems getting pregnant after the birth of their first child.
Whale is the common name for a widely distributed and diverse group of fully aquatic marine mammals. They are an informal grouping within the infraorder Cetacea, excluding dolphins and porpoises, so to zoologists the grouping is paraphyletic.dontocetes feed largely on fish and squid. A few, like the sperm whale, feed on large invertebrates, such as giant squid. Grey whales are specialized for feeding on bottom-dwelling molluscs. Male whales typically mate with multiple females every year, but females only mate every two to three years.
In fact the killer whale is the largest animal in the dolphin family and is one of the only known cetaceans to attack sharks, whales and other large marine animals, which helps explain why they are so well known and popular.he toothed whale suborder is comprised exclusively of whales, dolphins and porpoises that are born with teeth instead of baleen plates. While the killer whale carries the name âwhaleâ as part of its description this marine mammal is actually considered a dolphin.