Saved on this device

Follow your curiosity

What discovery has been shared with you?

FACTREE gives you something interesting to discover every day — and something worth talking about together.

Start with one fact. Explore it, go deeper, then follow whichever branch catches your imagination.

Choose subjects for a surprise

Exploring any topic

Begin your discovery

Your next discovery is one click away.

Choose one or more subjects above, or leave Any Topic selected and let curiosity decide.

Biology

The Evolution of Flightlessness in Island Birds and Its Ecological Consequences

Quick fact

Over 1,000 bird species have lost the ability to fly, most of them island dwellers. Since 1500, nearly all the birds that have gone extinct (about 90%) were flightless island species, a vulnerability directly linked to their loss of flight.

Why this is interesting

You know the kiwi, the bird that can't fly and has whiskers like a cat? How did it and many others lose the ability to do the one thing that most defines a bird?