Branching Line of Life

All living things on Earth are connected by shared ancestors that lived long ago. Over many generations, populations gradually changed in ways that helped them survive in different habitats.

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Age 16: open this week

In the picture

Single-celled organism at the line’s origin
Fish beside coral: a body suited to moving through water
Monkey’s hand on a branch: a grip suited to climbing
Lizard’s foot on desert rock: toes suited to gripping hot stone
Penguin’s wing in polar wind: a limb suited to cold water and ice

Examples

Different dog breeds, all descended from an ancient wolf-like ancestor.
Antibiotic resistance: bacteria that survive treatment pass on resistance.

Key takeaways

Species alive today share common ancestors.
Adaptations arise gradually as populations change over generations.

Carry on in the app

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