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Examples of Aquatic Mammals

There are about 6,400 different vertebrate mammal species still in existence. They include popular land mammals that humans like to keep as pets, such as dogs and cats.

This section focuses on the four taxonomic groups of aquatic mammals, defined as those that rely on some kind of marine ecosystem for their survival.

Fun Facts and Information about Mammals

First of all, it is important to understand that not all animals are "true mammals"!

Some fall under a different category (e.g. amphibians, fish, reptiles).

Here's the thing:

Mammals include a range of vertebrate species that are warm-blooded, have hair (or fur), and have young that drink milk.

Plus, mammal babies will be drinking the milk from the mother (unlike some birds and insects).

There are a few exceptions to the norm (see below). But, zoologists use several unique characteristics and traits to determine whether an animal is mammalian (of the breast) - or not! So, by and large, land and aquatic mammals:

Exceptions to Mammal Criteria

Despite being born without any hair or fur, whales (including the blue whale) are typical examples of mammals. In general, the hair grows while it's developing inside the womb. But, any hair growth tends to disappear towards the end of the fetal stage.

A to Z List of Marine Mammals

The oceans, and a few freshwater systems (e.g. the Amazon, Ganges), provide essential habitats for around 130 different species of marine mammals. We can divide them into the following taxonomic groups:

The facts and information in this section focuses on some of the most common aquatic mammal species, including:

Pro Tip: The largest mammal is the female blue whale, which can measure more than 30 metres (100 feet) in length and weight up to 190,000 kilograms (350,000 pounds). By comparison, the smallest mammal is actually the Etruscan pygmy shrew, which is only four (4) centimetres long and weighs less than 2 grams.

Related Information and Help Guides

Note: The main index section contains further information about sea life creatures with extra details about the threats they face from climate change and overfishing.

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