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What happened in the Cretaceous Period?

By |2019-04-29T06:34:15-07:00June 24th, 2017|Geology|

Volcano erupting When was the Cretaceous period? During the Cretaceous period, beginning about 145 million years ago, the continents continued to drift away from each other. Plate tectonics Back to the Jurassic Summary of geological eras All our geology articles What happened during the Cretaceous? Because the continents were separated, mammals, birds, and [...]

What is an aurochs? Central Asian Environment

By |2019-02-06T08:28:00-07:00May 31st, 2017|Central Asia, Environment|

Cave painting of a herd of aurochs (about 14000 BC) When did the aurochs evolve? Around fifty million years ago, after the dinosaurs died, large mammals started to evolve from smaller mammals that came earlier. Because grass had evolved only recently, about 100 million years ago, there weren't yet very many animals that ate grass, [...]

What are conifers? Pine trees, gymnosperms

By |2018-04-21T11:56:36-07:00May 30th, 2017|Biology|

Spruce tree - a type of gymnosperm and conifer Near the end of the Carboniferous period, about 300 million years ago, the land on Earth got a lot drier than it had been before. It was drier because plate tectonics was bringing all of the land together into one big continent, Pangaea. Plants that [...]

Flowering plants – Evolution and Biology

By |2019-06-11T04:54:00-07:00May 30th, 2017|Biology|

Flowering plants: Lavender flowers smell wonderful! Before there were flowers... For millions of years, the Earth was covered with ferns and pine trees and moss and mushrooms, without any flowers, grass, or fruit. Gymnosperms What is moss? What are mushrooms? Evolution of ferns All our biology articles When did flowers evolve? But about 120 [...]

Seeds – Plant reproduction – Biology

By |2018-04-13T17:51:52-07:00May 30th, 2017|Biology|

Evolution of seeds: Dandelion seeds What is a seed? A seed is the egg cell of a plant, with a hard wrapper around it so it can survive on its own. The earliest plants with seeds evolved from plants with spores during the late Devonian period, about 360 million years ago. The seeds [...]

How flowers reproduce – Plant Biology

By |2019-06-11T05:29:37-07:00May 30th, 2017|Biology|

Black-eyed Susan (the black in the middle is the seeds) - How flowers reproduce When did flowers evolve? The earliest flowers probably developed about 130 million years ago, in the Cretaceous period, as a way to attract newly evolved flying insects - mainly bees. When did bees evolve? The Cretaceous period All our [...]

What are dinosaurs? Evolution and Biology

By |2019-05-08T08:46:44-07:00May 26th, 2017|Biology|

A dinosaur skeleton: evolution of dinosaurs When did dinosaurs evolve? The first dinosaurs evolved out of earlier types of chordate reptiles about 230 million years ago, on the big land mass called Pangaea. Earlier chordates More about reptiles The Triassic period All our biology articles Cold-blooded or warm-blooded? Dinosaur eggs: evolution of [...]

What are arthropods? Biology

By |2019-02-03T21:35:07-07:00May 25th, 2017|Biology|

Bee on a flower What are arthropods? Insects, spiders, crabs, and lobsters are all arthropods, so there are a lot of arthropods on Earth. Annelid worms All our biology articles When were the first arthropods? The earliest arthropods on Earth developed about 550 million years ago. That was during the Proterozoic period. Proterozoic [...]

Why do grasshoppers jump? – Biology

By |2017-05-25T15:32:20-07:00May 25th, 2017|Biology|

Grasshopper sitting on a leaf When grasshoppers first evolved from earlier insects, about 300 million years ago, they lived in forests of huge ferns, and the main danger to grasshoppers came from frogs. Like frogs, grasshoppers evolved to be good jumpers.They ate mainly ferns. Grasshoppers jump by pushing with the big muscles in [...]

Why do ants eat bugs?

By |2019-01-28T06:42:41-07:00May 25th, 2017|Biology|

Evolution of ants: A bunch of ants When did ants evolve? Ants evolved from earlier wasps about 150 million years ago, during the Cretaceous period. The evolution of ants was around the same time that mammals were beginning to become common, soon after the dinosaurs died out. Go back to bees and wasps More [...]