Classification, Bones and Teeth

Life on earth is incredibly diverse. Scientists have named over 1.5 million species and many more have not yet been discovered. There are also countless species that have gone extinct. To try and understand the enormous diversity of life on earth (‘biodiversity’), some scientists study, name and classify living things. These drawers of beautiful beetles were assembled by Frederick Horniman (1835-1906), who founded this Museum and even had a beetle named after him! Beetles, a type of insect, have a protective exoskeleton on the outside of their bodies instead of internal bones. Insects make up around 75% of all known animal species. How many can you name?

Humans, along with other mammals, are classified as ‘vertebrates’ because they have internal skeletons. Human babies are born with approximately 300 bones, whilst the skeleton of an adult human has around 206. How does this happen? As babies grow, some of their bones fuse together to make bigger bones. The longest human bones are the femurs (thigh bones), whilst the smallest bones are inside the ears. How many bones can you name? Humans and other animals have many of the same bones. In the Natural History Gallery, compare the human skeleton those of some other animals. Which bones can you spot in different skeletons?

A bird's skeleton has a tough job as it needs to be light enough for flight, but strong enough to take the strain of flying. The weight of a bird’s skeleton is often lighter than the weight of its feathers! Most birds have thin, almost hollow bones that are strengthened by a criss-crossing internal structure. Their strong bones also support their muscles to ease the strain of flying. What other features do birds have?

Like most other mammals, bats have fur, are warm-blooded and give birth to live young. However, bats are the only mammals that can truly fly! Their flexible wings are made up of a thin skin stretched over lightweight arm and finger bones. Other mammals, including flying squirrels and sugar gliders, may appear to fly through the air, but actually glide. In the Natural History Gallery, compare the flying bat to the gliding mammals, how are they different?

Have you seen a grass snake? They are one of the few native snake species that live in England and are harmless to humans. Grass snakes are classified as reptiles as they have scaly skin, are cold blooded, and lay eggs with leathery shells. They bask in the sun to warm their bodies and hibernate during the winter. Grass snakes are strong swimmers and are often found near water. Sadly, due to habitat loss, these animals are thought to be in decline. To help, you could leave areas of gardens wild or create a pond. Which other reptiles live in the UK?

How would you classify a platypus? This Australian animal has a beaver-like tail, furry body, flat beak and webbed feet. Females lay eggs, whilst males have a venomous spike on their back legs! The platypus is a unique Australian species. Along with echidnas, platypuses are grouped in a separate order of mammals called monotremes, which are different from all other mammals because they lay eggs. When the platypus first came to the attention of scientists, its unusual look caused a lot of confusion and many people believed that the animal was a fake! You can find an echidna in the Natural History Gallery, and also a fake animal called a merman in the World Gallery.

Sharks’ teeth are essential to their survival. In the Natural History Gallery you can find many different types of shark teeth. Sharks’ teeth vary in shape and size depending on their prey and the size of the shark. The blue shark has pointed, serrated, teeth for cutting large prey into smaller portions that can be easily swallowed. The smaller Port Jackson shark lives in the waters around Australia and feeds mainly on hard-shelled creatures. It has small, pointed teeth at the front for clutching prey, and flat, wide grinding teeth at the back. Most shark’s teeth never stop growing; new teeth are stored in rows within the gum so that, when one breaks, another can take its place. One shark can grow hundreds of teeth in its lifetime. Why is this so important? Across the world, shark teeth can often be found on beaches and are sometimes used by different groups of people to decorate precious objects. You can find one of these objects, a shark tooth sword, in the Oceania encounter of our World Gallery.

Elephants have amazing teeth. In their mouths are four huge molars that are gradually worn down by relentless grinding. Luckily, elephants can replace each molar up to five times. As a newly grown molar emerges, it pushes out the old one, which the elephant simply spits out! Tusks are actually elongated incisor teeth that keep growing throughout their adult life. Elephant tusks have a variety of uses: as a tool to dig for food or water and to strip bark from trees; as a weapon in battles with rivals; and to attract other elephants. Elephants are endangered due to habitat loss and are hunted for their ivory tusks. The Horniman cares for many old objects made of ivory such as piano keys, a flute and ornaments. How do you feel about objects made of elephant ivory?

Throughout human history, people have used bone and ivory to make things. Bone is an easy material for people to find and is often left over after a meal or hunt. Bone is strong but can be carved easily and can be used to make tools, weapons, jewellery and musical instruments. This bone instrument was made over 3,500 years ago in ancient Egypt. Bone instruments are still made and played today. Ivory has been used to make flutes, castanets and trumpets to name a few, however, this is less common today. Why? Explore the Music Gallery at the Horniman Museum to discover more bone and ivory instruments from around the world.

Crocodiles have only one type of tooth whereas humans have four. Can you name all four types? Crocodiles use their teeth grasp and crush their prey rather than to chew it, so some crocodiles swallow stones to grind the food in their stomachs. This object is a Nile crocodile skull. They have sharp teeth and a very powerful bite. In the ancient Kingdom of Benin, crocodiles were seen as policemen who guarded the waters and protected the king.