BIO Exam 4 Study Guide

Front

Where do river dolphins occur?

Back

Ganges, Indus, Yangtze, and Amazon rivers.

Front

When did Sirenians and Cetaceans originate?

Back

50-55 million years ago.

Front

When did sea otters evolve?

Back

5-7 million years ago.

Front

Which group of animals are Sirenia most closely related to?

Back

Elephants and hyraxes.

Front

When did Cetaceans diverge from other artiodactyls?

Back

50 million years ago.

Front

What are Sirenians?

Back

A group of marine mammals that includes manatees and dugongs.

Front

What is the primary habitat of Sirenians?

Back

Shallow coastal waters and rivers.

Front

What adaptations do Cetaceans have for aquatic life?

Back

Streamlined bodies, flippers, and blowholes.

Front

What is the significance of the Ganges River for river dolphins?

Back

It is one of their primary habitats.

Front

What are the main threats to river dolphins?

Back

Habitat loss, pollution, and fishing nets.