Nepedia
Back to Discover
Fluent Reader
🧬

Auk

life science Maturity 5-7 Next article →

Auks are amazing seabirds found in the cold Northern Hemisphere.

Auks
Auks

They belong to the family Alcidae. This family includes many birds like puffins, auklets, and murres. There are 25 species in this family that are living or were recently extinct. Most auks can fly through the air. However, they are even better at swimming and diving. When they are underwater, they look like they are flying through the sea.

Puffin Mrkoww
Puffin Mrkoww

To move through the water, auks use a method called pursuit diving. This means they use their wings to push themselves forward to catch prey. Their wings are a special compromise between two different jobs. They are built to be good for diving, but they are also just enough for flying. Because their wings are short, they must flap them very quickly to stay in the sky. Some birds, like the Uria guillemots, are very efficient at diving. Others, like puffins, are better at flying and walking on land.

Alca torda Roest 2003
Alca torda Roest 2003

Scientists have studied how auks changed over a very long time. Long ago, people thought auks were a very old group of birds. Now, genetic studies show they changed from wading shorebirds into diving seabirds. This happened because of strong natural selection. Their closest living relatives are likely the skuas. These two groups split apart about 30 million years ago. This shows how much a bird can change to fit its home.

Blackguillemot44
Blackguillemot44

We can learn about the past from very old fossils. The earliest clear fossils of auks are from the late Eocene, about 35 million years ago. Some fossils have been found in places like California and Maryland. Scientists believe auks likely first evolved in the Pacific Ocean. They probably moved to the Atlantic Ocean by traveling south. Most modern auks stay in the cool waters of the north. They cannot hunt well in warm water because the fish swim too fast.

Xantus adult
Xantus adult

Most auks spend their adult lives on the open sea. They only come to land when it is time to breed. Many auks are monogamous, which means they stay with one partner for life. They usually lay only one egg each year. Some species live in large colonies on steep cliff edges. Other birds, like the puffins, make nests in burrows.

Marbled murrelet breeding plumage
Marbled murrelet breeding plumage

These different ways of living help them survive in the ocean.

383 words

Where will your curiosity go next?

Keep exploring at your chosen reading level.

🖼️ Images & Media (6)
File:Auks.jpg
Auks.jpg
File:Alca torda Roest 2003.jpg
Alca torda Roest 2003.jpg
File:Puffin Mrkoww.jpg
Puffin Mrkoww.jpg
File:Xantus adult.gif
Xantus adult.gif
File:Blackguillemot44.jpg
Blackguillemot44.jpg
File:Marbled murrelet breeding plumage.jpg
Marbled murrelet breeding plumage.jpg
More to explore

✨ What else?

Related topics you might enjoy

🔬 Go deeper

More advanced topics to explore

🪜 Step back

Simpler topics to build understanding

What is Nepedia?

A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.