Here at AnimalFacts.net you will find a collection of interesting facts about animals.
By studying fossils and DNA samples, we are able to learn more and more about animals, both living and extinct, every day.
New animals are discovered every year, and new features and aspects of animal behavior are frequently documented.
In fact there are practically no animals on Earth that we know absolutely everything about, so even the more common creatures you observe in your backyard still hold many secrets yet to be unveiled.
What are animals?
Generally, an animal is a living creature that is able to move of its own volition (by choice).
The word "animal" is derived from the same root as "animat"' - to move, or make move - which itself is from the Latin "animatus", the past participle of "animare" - to give life to - from "anima" - breath.
The following creatures are all examples of animals. Of course, humans are animals too!
Technically, animals are living organisms which have all of the following characteristics:
- They are made up of more than one cell (are multicellular).
- They are eukaryotes. This means that their cells have a nucleus which contains genetic material. Such cells are known as eukaryotic cells.
- Animals are heterotrophs - they gain energy by taking in carbon-based compounds from other organisms.
- Animals can move about by themselves during part or all of their lifetimes.
Here is a selection of animal facts:
- Animals live on every continent on Earth, as well as in its oceans.
- Human beings are animals, of the species Homo sapiens. Our genes show that our closest living relatives are chimpanzees.
- The first animals to appear on Earth are believed to have been sponges. Scientists have found chemical remains of sponges that lived over 600 million years ago.
- Fossils show that most major groups of animals appeared on Earth during the Cambrian explosion, about 530 million years ago.
- The blue whale is the largest living animal.
- The African elephant is the largest animal that lives on land.
- The largest land animals to have ever lived were dinosaurs known as sauropods.
- The giraffe is the tallest living animal on earth.
- One of the smallest animals in the world is a wasp, Dicopomorpha echmepterygis. Males are only about 1/7 of a millimeter long.
- The bootlace worm, a type of ribbon worm, can grow up to 200 feet long. It is the longest animal on Earth.
- A clam that lived to be a little over 400 years old had the longest lifespan of any animal that we know about.
- The gastrotrich, a microscopic animal that lives in fresh and saltwater, lives for about three days. It has the shortest lifespan of any living animal.