Biological Evolution: Unity and Diversity

Animals

Scientists still aren’t always sure why dogs wag their tails

Your dog is wagging its tail. That must mean it’s happy, right? Maybe not. Scientists know less about what’s behind this behavior than you might think.

Life

Bacterial fossils exhibit earliest hints of photosynthesis

Microscopic fossils from Australia suggest that some bacteria evolved structures for oxygen-producing photosynthesis by 1.78 billion years ago.

Animals

A newfound type of hedgehog is small, dark and adorable

At first, this hedgehog was mistaken for a lookalike relative. But its teeth, skull shape and DNA confirmed it as a new species.

Animals

Here’s how kingfishers avoid concussions during high-speed dives

Understanding the genetic adaptations that protect the birds’ brains as they dive might one day offer clues to protecting human brains.

Animals

Horned lizards and snakes tend to ambush their prey

The reptiles’ horns could help or hinder during foraging, depending on how they hunt. This might be why horns evolved in some species and not others.

Life

Scientists Say: Ichnology

This field of science looks to understand life — past and present — by studying how organisms altered their surroundings.

Animals

Let’s learn about why turkeys are dinosaurs

Modern birds are the only dinosaurs that survived an apocalyptic extinction event 66 million years ago.

Humans

Scientists Say: Prehistoric

Researchers rely on prehistoric tools and other artifacts to study the vast stretches of time before recorded history.

Math

Bees and wasps devised the same clever math trick to build nests

During nest building, these insects add five- and seven-sided cells in pairs. This helps their colony fit together hexagonal cells of different sizes.

Oceans

How would a mermaid sound underwater?

Human ears don’t work well in the water. A mermaid would need marine creature features to talk to and understand her aquatic friends.

Fossils

This bizarre ancient predator snagged soft prey

Scientists are rethinking how this extinct creature used the spiky limbs sticking out of its face to hunt.

Animals

Megalodons may have become megahunters by running hot

O. megalodon sharks were warm-blooded mega-predators. But when food sources dwindled, colder-blooded sharks may have had an evolutionary edge.