Adaptation This is a change in an animal, caused by evolution. An adaptation can be a change in the body (such as stripes on a zebra or wings on a bird) or it can be a behaviour (such as wolves hunting in packs and fish swimming in shoals). An adaptation helps an animal or species survive.
Aquatic Means to do with the water. An aquatic animal is one that lives in the water, like a fish. If something is semi-aquatic, then the animal spends some time in the water and some time on the land. A crocodile is semi-aquatic.
Convergent evolution This is where two things that are not very closely related evolve to have a similar adaptation. The best examples of this are the wings of birds, bats and pterosaurs. These animals are not very closely related but have all evolved wings because they’re the best things to allow an animal to fly.
Divergent evolution This is where several closely related species (that all share something in common) start to change, so that they can live in different habitats or move or hunt in different ways. A good example of this is mammal limbs. All are closely related but the original mammal limb (with five digits) has changed and now there are bat wings, horse hooves, whale flippers and your own hands. They all look so different but all evolved from the same thing.
Ectothermic This means ‘cold blooded’ but it’s a rubbish term, really. The animal still has warm blood but it means the animal warms its body up from the outside environment. A snake is ectothermic, using the sun to warm its body up for energy.
Endothermic This means ‘warm blooded’ – also a rubbish term. Because ecothermic animals also have ‘warm’ blood, it doesn’t tell us much. Really, being endothermic means you can make your own heat inside your body. All mammals, for example, are endothermic.
Geologist A scientist who specialises in geology.
Geology This is the science that looks at the Earth and how it works. It especially examines the different types of rocks that are found in different parts of the world and what they can tell us.
Isotope There is lots that can be said about isotopes. It’s a bit complicated and you need to understand some chemistry and physics to really appreciate them. Basically, isotopes are elements that have been changed slightly from what they originally were. For example, not all hydrogen atoms are the same. There are different types of hydrogen, with different numbers of neutrons. These are tiny particles that don’t have an electrical charge. So, there is hydrogen-1, hydrogen-2, and hydrogen-3. Some of these break down faster than others and can be used by palaeontologists not only to look at the age of fossils but also to see where they lived and even what they ate.
Vertebrae These are the backbones in an animal. Lots of vertebrae make the spine. A single one is a vertebra.