1.Where do the dolphin live?
2.what do the dolphin look like?
3.What do the dolphin eat?
4.Are there anything special about the dolphin?
- ?Lv 61 十年 前最佳解答
Dolphins are aquatic mammals that are closely related to whales and porpoises. There are almost forty species of dolphin in seventeen genera. They vary in size from 1.2 metres (4 ft) and 40 kilograms (88 lb) (Maui's Dolphin), up to 9.5 m (30 ft) and ten tonnes (the Orca or Killer Whale). They are found worldwide, mostly in the shallower seas of the continental shelves, and are carnivores, mostly eating fish and squid. The family Delphinidae is the largest in the Cetacea, and relatively recent: dolphins evolved about ten million years ago, during the Miocene. Dolphins are considered to be amongst the most intelligent of animals and their often friendly appearance and seemingly playful attitude have made them popular in human culture.
1 Origin of the name
2.1 Hybrid dolphins
3 Evolution and anatomy
4.1 Social behaviour
4.2 Reproduction and sexuality
Various methods of feeding exist, not just between species but also within a species various methods may be employed, some techniques being used by only a single dolphin population. Fish and squid are the main source of food for most dolphin species, but the False Killer Whale and the Killer Whale also feed on other marine mammals.
One feeding method employed by many species is herding, where a pod will control a school of fish while individual members take turns plowing through the school, feeding. The tightly packed school of fish is commonly known as bait ball. Coralling is a method where fish are chased to shallow water where they are more easily captured. In South Carolina, the Atlantic Bottlenose Dolphin takes this one step further with what has become known as strand feeding, where the fish are driven onto mud banks and retrieved from there. In some places, Orcas will also come up to the beach to capture sea lions. Some species also whack fish with their fluke, stunning them and sometimes sending fish clear out of the water.
Reports of cooperative human-dolphin fisheries date back to the ancient Roman author and natural philospher Pliny. A modern human-dolphin fishery still takes place in Laguna, Santa Catarina, Brazil.
4.5 Jumping and playing
5 Threats to dolphins
5.1 Natural threats to dolphins
5.2 Human threats to dolphins
6 Human-dolphin relationships
6.6 2007: Year of the Dolphin
8 External links
Killer Whales, also known as Orcas
The Boto, or Amazon River Dolphin
See also: List of dolphins資料來源： Wikipedia