Leah+Spingarn

**__Human Evolution__**

The world is about 4.6 billion years old. The humans have only been on Earth for the last 60,000 years. Where did we come from? How did we get here? Well I am about to tell you. Humans are primates, just like apes, monkeys and lemurs. A __//**primate**//__ is a type of mammal with opposable thumbs and binocular vision. Binocular vision is when an animal’s two eyes are located in the front of the head and provide three-dimensional vision. Scientist believe humans evolved from primates. http://images.google.com/imgres?imgurl=http://benskerrett.com The first a primate may have existed with the dinosaurs. These mammals probably resembled a mouse like creature that was active at night, lived in trees and ate insects. Today's scientist think the chimpanzee is the closest living relative to the human. This means that humans and chimpanzees share a common ancestor. Somewhere between 6 million and 30 million years ago the first ancestor of humans, apes and chimpanzees started to evolve into what they are today. Later this creature split off into different species, including humans and chimpanzees. http://www.biomechanics.bio.uci.edu/_html/nh_biomech/running/running.ht http://www.biomechanics.bio.uci.edu/_html/nh_biomech/running/running.htm Humans are not only primates, but in addition they are in a more specific category called __//**hominids**//__. Hominids are a type of primate. The largest characteristic that separates hominids from other primates is bipedalism or the ability of walk upright on two feet, like humans do. Hominids can also be defined by the shape of their skeletons. They have long lower limbs like legs and no tail. http://www.amnh.org/exhibitions/permanent/humanorigins/history/humans5.php They have found many different fossils of ancient hominids and have named eighteen of them. Scientist can classify a fossil into the hominid family when that fossil shares certain characteristics with the modern human skeleton, for example size, shape of skull, pelvis and other traits.

The earliest hominid fossils have been found in Africa leading scientist to believe that hominids evolution started in Africa. These fossils are 6 million to 7 million years old. Many of these early hominids are what we call //__**australopithecines**__//. Australopithecines were similar to apes, yet different. Their brains were slightly larger than the brain of an ape. Some of them may have even been smart enough to build their own stone tools. In addition, they climbed trees and walked on two legs. Australopithecines and other types of hominids may have lived at roughly the same time. Many australopithecines had a humanlike jaw and slender bodies, but still had the apelike skull. They most likely lived in the forests and grasslands and ate a vegetarian diet. Many scientists believe that australopithecines later became the modern human. http://www.museumstorecompany.com/product_info.php?products_id=1802 About 2.4 million years ago a new group of hominids started to roam the planet. These hominids were slender as the australopithecines were, but were more humanlike. For example, they had larger and more complex brains, rounder shoulders and flatter faces than the australopithecines. This new group is called homo. The homo group includes the modern human. Members of this group existed all over the planet. Not only did they walk upright, but in addition, they left behind evidence of advanced tool making. These new hominids may have adapted to the climate change by moving to new locations. This group gradually evolved over time.

2.4 million years ago with the __//**homo habilis**//__. 1.8 million years ago the **__//homo erectus//__** appeared. The homo erectus was capable of growing as tall as the modern human. No one knows what these mammals really looked like, but scientist have made guesses by the way the skulls and fossils are shaped.

As early as 30,000 years ago, two types of hominids were left on Earth. Both had the largest brain of any hominid. Scientists know this because these hominids left behind advanced tools, clothing and art. Most scientist think that humans evolved from one of these two species.

One of these to relatively recent hominids is known as the __//**neanderthals**//__. Neanderthals lived in Europe and Asia. They tried to care for the sick and elderly to the best of their abilities and buried their dead. Neanderthals first appeared 230,000 years ago. 30,000 years ago they disappeared and no one knows why. http://www.sciencemuseum.org.uk/antenna/neanderthal/ The most recent group of hominids none to man kind is the __//**homo sapiens**//__. Modern humans are homo sapiens. The earliest of these homo sapiens lived in Africa 100,000 to 160,000 years ago. These early homo sapiens had flatter faces and a more rounded skull than the Neanderthals. The earliest of these homo sapiens started creating sculptures, carvings, paintings, and clothing and have kept improving their methods to this day. http://www.terrestrialextras.com/

If you want to know more: Fun Games: http://www.pbs.org/wgbh/aso/tryit/evolution/

Other Web Sites: http://www.pbs.org/wgbh/evolution