Fossil Evidence for Evolution

What is a fossil?  A fossil is a physical remain of an ancient organism.  The study of fossils is called paleontology. Fossils of a fish and a wasp.

How are fossils made?  The organism dies and is covered by mud, dirt or rock.  The body starts to decay, caused by bacteria metabolizing the organic material.  If few bacteria are present, mineral replacement occurs and eventually the organism becomes rock.  Many times there are too many bacteria and the organism decays before fossilization can occur.  Because of this, the fossil record is far from complete.

Soft Tissue Fossils  Soft tissue can sometimes make a fossil record if it leaves an impression in mud that hardens and is preserved  Soft tissue fossils can also happen in ice or amber, where the actual organism was preserved  For example, insects in amber or wooly mammoth in Arctic ice

Extinction  Extinction is when the last living member of a species dies out  Extinctions have been happening at a much faster rate  This is due to the increase in human population- hunters, decrease of habitat ie; passenger pigeon A passenger pigeon.

How do fossils provide evidence for Evolution?  Fossils provide physical records of organisms that are not alive today.  These are very helpful for scientists to study body structures of ancient organisms and relate them to modern species.  Fossils also are evidence of the rate of evolutionary change.  Fossils in intermediate stages between species and their ancestors give clear evidence of evolution. Fossils of feathered dinosaurs found in China reveal some evolutionary stages between dinosaurs and birds.