Where did dolphins come from?

Question

I'm doing a project on evolution and i need help i cant fing anything!!!

Answer 1

You can't find *anything*???

Uhm ...
1. Go to www.google.com (or go down to the bottom of the same page in which you asked this question ... there's a Search the Web feature there).

2. Type "dolphin evolution".

3. I just did this and I got 1,250,000 hits.

Here is the one at the top of the list. It's got what you need:
http://www.wiu.edu/users/emp102/DolphinWeb/dolphin_evol.html

Here were the next two on the list ... both very good:
http://library.thinkquest.org/17963/evolution.html
http://www.ucmp.berkeley.edu/mammal/cetacea/cetacean.html

And you even get a joke one from The Onion ... it's hilarious:
"Dolphins Evolve Opposable Thumbs"
http://www.theonion.com/content/node/28315

Answer 2

It is generally believed that all marine mammals evolved from land based ancestors around 50-60 million years ago. Of all the marine mammals the dolphins are among those most adapted to an aquatic way of life. All cetaceans were well diversified around 50 million years ago. It is widely accepted in scientific circles that both the baleen and toothed whales shared a common ancestor, now extinct. The closest living relatives of dolphins today are the even toed ungulates such as camels and cows with the humble hippopotamus being the closest living relative. The origin of dolphins and the origin of whales in general is the subject of much debate. Did they evolve from an ancient ungulate order or did they diverge along with the hippopotamus from another lesser known group of animals land based ungulates?

Answer 3

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 m (4 ft) and 40 kg (88 lb) (Maui's Dolphin), up to 9.5 m (30 ft) and ten tonnes (the Orca). 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, along with whales and porpoises, are thought to be descendants of terrestrial mammals, most likely of the Artiodactyl order. Dolphins entered the water roughly fifty million years ago. Dolphins have a streamlined fusiform body, adapted for fast swimming. The basic coloration patterns are shades of gray with a light underside and a distinct dark cape on the back. It is often combined with lines and patches of different hue and contrast.

Answer 4

Dolphins are mammals, so the theory is they came from land, like whales.

Answer 5

Most people say Detroit....but I say Cleveland......