Silurian

/Tag: Silurian
17 08, 2017

Levers – Simple machines – Physics

By |2018-05-31T11:49:33-07:00August 17th, 2017|Physics|1 Comment

Levers: An orangutan child using a stick as a lever What is a lever? A lever is basically just a long stick that you push or pull against a fulcrum - a fixed object - to move something. A lever helps you move something heavy, or make something go fast. The earliest levers developed [...]

25 06, 2017

Silurian period – Fish get jaws

By |2018-04-19T11:29:11-07:00June 25th, 2017|Biology - Evolution, from cells to modern mammals, birds, and reptiles, Geology|0 Comments

Silurian period: Trout swimming When was the Silurian period? The beginning of the Silurian period was about 443 million years ago. Some environmental problem at the end of the Ordovician period (probably ice ages) killed most of the plants and animals on Earth. The creatures that survived this extinction were the ones that [...]

26 05, 2017

What does my liver do? Evolution and Digestion

By |2017-05-26T18:01:56-07:00May 26th, 2017|Biology - Evolution, from cells to modern mammals, birds, and reptiles|0 Comments

Fish liver The earliest beginnings of what became the liver may have been relatives of segmented worms that lived about 600 million years ago. These worms evolved to have sections of their intestines that pinched out and made two little bags. Probably the worms used the bags to keep extra fat in, for when [...]

26 05, 2017

Digestive System – Biology and Evolution

By |2019-05-07T20:07:23-07:00May 26th, 2017|Biology - Evolution, from cells to modern mammals, birds, and reptiles|0 Comments

Digestive system: A hydra eating: the mouth is where all the tentacles come together,near the center of the picture.The hydra is eating the round bug in its stomach. Before digestive systems... Starting about 3.8 billion years ago, during the Archaean Era, one-celled creatures were the earliest living things. They just floated in the ocean [...]