https://padlet.com/johnedwa111/3eu8hw3uc6wg Grade 10 Science Evolution Task en-us 2016-10-29 07:28:34 UTC 2025-09-24 22:10:58 UTC hello@padlet.com johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025121 "Lucy” was discovered in 1974 in Ethiopia and belongs to genus Australopithecus and is a possible ancestor. She is about 1m tall and 3 million years old.She is probably among the earliest hominids to use bipedal gait. Fossilized footprints of  Australopithecus afarensis were discovered in 1976 at Laetoli in Tanzania and were made in volcanic ash 3.6 million years ago.

]]> 2016-10-29 07:32:33 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025121 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025238 2016-10-29 07:37:26 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025238 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025265 2016-10-29 07:38:19 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025265 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025412 The imprints show typical bipedal foot development with a heel to toe movement and a large big toe parallel to the other toes.]]> 2016-10-29 07:43:01 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025412 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025481 2016-10-29 07:45:30 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025481 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025524 In comparison to a chimpanzee the human foot has also developed arches which are rigid and pliable depending on the need.]]> 2016-10-29 07:47:08 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025524 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025659 For bipedal gait other skeletal structures need to change.

]]> 2016-10-29 07:51:24 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025659 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025806 Chimpanzees sway as they walk because their feet are spaced apart and they have to shift their centre of gravity over each foot with each step. Humans have an angle at the neck of the femur which brings the feet close together.

]]> 2016-10-29 07:57:12 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025806 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025854 Comparison of chimpanzee , Australopithecus and homo sapiens indicates that Lucy had legs made for bipedal gait.  Another  feature is the position of the foramen magnum

]]> 2016-10-29 07:59:37 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025854 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025941 The lumbar spine has a curve which is not present in apes.]]> 2016-10-29 08:02:07 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134025941 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134026266 2016-10-29 08:12:20 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134026266 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134026273 2016-10-29 08:12:40 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134026273 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134026314 When our human ancestors moved from being forest tree dwellers to living on grasslands, they had to compete with carnivores which had been adapted to that environment for millions of years. The carnivores had many advantages over us, examples include: better sense of smell, vision adapted for detecting movement, more acute hearing, built for speed and with teeth designed to hold and tear prey. In order to compete the early hominids had to think better.

]]> 2016-10-29 08:13:32 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134026314 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134026572 This needed a larger brain. During the course of human history brain size tripled. Lucy had a brain size of about 450cm. Modern humans have a brain size of about 1350cm3. There is evidence to suggest that brain size has actually fallen in the last 20000 years which could be due to a smaller body mass, improved “wiring” or due to the growth of supporting communities so an individual does not have to depend on themselves so much. The climate seems to have affected growth of the brain because changes in the environment put pressure on individuals to adapt.

]]> 2016-10-29 08:22:28 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134026572 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134026587 2016-10-29 08:23:05 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134026587 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069252 2016-10-30 07:57:48 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069252 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069253 2016-10-30 07:57:51 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069253 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069313 The human brain grows very slowly in homo sapiens only reaching maturity at about 25 years of age.]]> 2016-10-30 07:59:40 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069313 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069421 Increased brain size led to the development of fire, tools and planning for hunting and gathering and the development of art.]]> 2016-10-30 08:02:24 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069421 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069472 2016-10-30 08:04:17 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069472 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069500 2016-10-30 08:05:08 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069500 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069607 The invention of fire made it possible to cook food requiring less chewing ability needed. Success at hunting also meant that tooth size like large grinding molars could be reduced. Powerful jaws were no longer needed and so muscles became smaller and bones they attached to in the face became smaller. Canine teeth used to kill or injure by biting were replaced by spears and flint stone.]]> 2016-10-30 08:09:03 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069607 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069637 2016-10-30 08:10:25 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069637 johnedwa111 https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069815 Smithsonian institution. 2016. What does it mean to be human. [ONLINE] Available at: http://humanorigins.si.edu/. [Accessed 28 October 2016].

Melissa Hogenboom. 2014. The 'Lucy' fossil rewrote the story of humanity. [ONLINE] Available at: http://www.bbc.com/earth/story/20141127-lucy-fossil-revealed-our-origins. [Accessed 27 October 2016].

Science Go. (unknown). Laetoli Footprints. [Online Video]. 29 October (known year). Available from: http://www.sciencechannel.com/tv-shows/greatest-discoveries/videos/100-greatest-discoveries-laetoli-footprints/. [Accessed: 29 October 2016].

Jeffrey P. Bigham. 2005. ManticMoo. [ONLINE] Available at: http://www.manticmoo.com/articles/jeff/scholarly/an-evolving-human-dentition.php. [Accessed 30 October 2016].

Morris, D, 1967. The Naked Ape. (unknown) ed. Great Britain : Vintage.]]> 2016-10-30 08:16:17 UTC https://padlet.com/johnedwa111/3eu8hw3uc6wg/wish/134069815