HS-LS4-1
Communicate scientific information that common ancestry and biological evolution are supported by multiple lines of empirical evidence.
- Fossils
These crocodile ancestors lived a two-legged life
A set of 106-million year old footprints show a crocodile relative appears to have walked on two legs.
- Fossils
Tube-dwelling sea creatures may be oldest known parasites
A fossil bed of clam-like animals from a half-billion years ago is covered in tube-dwelling organisms. These suggest the tube dwellers were parasites, scientists now report.
- Archaeology
This cave hosted the oldest known human remains in Europe
Bone fragments, tools and other finds in Bulgaria suggest that Homo sapiens moved rapidly into Eurasia as early as 46,000 years ago.
- Fossils
Saber-toothed anchovy relatives were once fearsome hunters
Today’s plankton-eating anchovies sport tiny teeth. But their ancient kin were armed with spiky lower teeth and a giant upper sabertooth.
- Chemistry
Ancient recipes helped scientists resurrect a long-lost blue hue
Led by medieval texts, scientists hunted down a plant and used its fruit to make a blue watercolor with mysterious origins.
- Fossils
This dinosaur was no bigger than a hummingbird
The skull of one of these ancient birds — the tiniest yet known — was discovered encased in a chunk of amber originally found in Myanmar.
- Genetics
What would it take to make a unicorn?
Onward’s dumpster-diving unicorns seem like an impossibility. But scientists have some ideas about how unicorns could become real.
- Fossils
Small T. rex ‘cousins’ may actually have been growing teens
Dinosaurs once thought to be mini cousins of Tyrannosaurus rex may have been merely adolescent members of the famous species, a new study suggests.
- Animals
Piranhas and plant-eating kin replace half their teeth at once
Piranhas and pacus shed and replace half of their teeth at a time. New teeth lock together as they push up from the jaw.
- Animals
Blood vessels in their heads kept big dinos from overheating
Giant dinosaurs evolved several ways to cool their blood and avoid heatstroke.
- Earth
Explainer: Understanding geologic time
Geologic time is unimaginably long. Geologists puzzle it out using a calendar called the Geologic Time Scale.
- Genetics
DNA tells tale of how cats conquered the world
Ancient DNA study suggests that domesticated cats spread across the ancient world in two waves.
