A species is a distinct group of organisms and the most basic unit used to measure life on Earth. However, there’s no single definition of a species, meaning this vital concept in biology can be difficult to understand. Find out the different ways scientists have of describing what species are, how they form and how many there are on Earth.

Convergent evolution occurs when species independently evolve similar traits. It’s a fascinating window into the power of natural selection.

What are the northern lights? The northern lights is the name given to the colourful lights that can appear in the night sky over the northern hemisphere. When they appear in the southern hemisphere, they’re called the southern lights instead. This phenomenon is known as an aurora. The northern lights are more formally known as the …

Not all jellyfish play by the same rules, and one species may have discovered the secret to immortality. How does the immortal jellyfish live forever? The life cycle of most jellyfish species is similar. Museum curator Miranda Lowe explains, 'They have eggs and sperm and these get released to be fertilised, and then from that you get a free-swimming larval form. 'The larva will move about in ...

Visiting the Natural History Museum is free. Book a ticket before your visit for the best experience, especially during our busy times. We do reserve space for walk-up visitors, but you may have to wait longer to get in.

Carbon dioxide (CO2) is a greenhouse gas. Find out what this means and why carbon dioxide has such a big impact on global temperatures.

Book tickets. Explore our galleries, science, news, videos and amazing images. South Kensington Tube. London, UK.

Find out what climate change is, why it matters and what it could mean for our collective future. What are weather, climate and climate change? Weather refers to atmospheric conditions, such as rain or snow, happening in a place at a specific moment in time. Climate is how much, on average, a type of weather will occur over a longer period. …

Homo habilis is a mysterious extinct ancient human that was named ‘handy man’ because it was once thought to be the first maker of stone tools. Discover what we know about this species.

Explore some of the discoveries that changed how we view dinosaurs and revealed the direct link between modern bird species and theropod dinosaurs.