Tess+Anderson

Have you ever wondered how humans evolved? Well, scientific studies have shown that humans, apes, and monkeys are all related and that they share a common ancestor. This ancestor lived around 45 million years ago. Scientists have studied fossils that link humans and apes together. Also, did you know that humans are actually classified as primates? Primates are a group of mammals that include all animals similar to humans, (apes, monkeys, and lemurs). We humans were not alive until after the dinosaurs died out. Scientists believe that chimpanzees, which are a type of monkey, are the closest living relative of humans. There wasn’t a noticeable difference between the appearance in both humans and chimpanzees until between 6 million and 30 million years ago.

Click below to see the timeline of human evolution: http://web.mit.edu/ealba/www/hominidtimeline.jpg

HOMINIDS

Do you know what hominids are? Well if not, I’ll explain it to you! Hominids include humans and their humanlike ancestors. The way you can tell whether or not an animal is humanlike is by bipedalism. This long and complicated word really just simply means “walking somewhat upright on two feet.” Eighteen different types of hominids have been found through fossils. The earliest hominids have features (traits) that are more humanlike than apelike. These features include the ability to walk upright as well as smaller teeth, flatter faces, and larger brains than earlier primates. Fossils of the oldest hominids have been found in Africa. This makes scientist think that hominid evolution began in Africa over 8 million years ago.

Click below to see what the transformation to bipedalism is like: http://www.bfro.net/REF/THEORIES/MELD/evolve1.gif

AUSTRALOPITHECINES

Most of the earliest hominids are classified as Australopithecines. The members within this group differ from apes in many ways. For example, their brains were slightly larger than apes. Scienitists think that some of them may have used stone tools. Also, they climbed trees but still were able to walk on two legs. Evidence has been found through fossils in several places in Africa. The fossils have shown us that the Australopithecines were alive 3 million years ago. Some of these creatures had slender bodies. They resembled both humans and apes because their jaws were more humanlike, but their skulls were smaller like apes. They may have lived in forests and grasslands. Their everyday meals were all vegetables and no meat. Scientists believe that humans evolved from these kinds of hominids.

Click below to see what Australopithecines looked like: http://library.thinkquest.org/26157/austrman.jpg

GLOBAL HOMINIDS

About 2.4 million years ago, a new group of hominids appeared. These hominids were very similar to the more slender hominids but they were more humanlike. The difference between these hominids and the more slender hominids was that they had larger and more complex brains, rounder skulls, and much flatter faces. These hominids were a member of the group Homo, which includes modern humans as well. The members of this Homo group ate all different kinds of food. One of the earlier members of this group was called Homo habilis. The Homo habilis lived 2.4 million years ago. About 1.8 million years ago, a new hominid appeared called the Homo erectus. This kind of hominid was able to grow as tall as modern humans do.

Click below to see a picture of the Homo erectus: http://humanisthall.net/HomoErectus1.jpg

NEANDERTHALS

One of the more recent hominids is called the Neanderthals. They lived in Europe and Western Asia. Neanderthals may have lived as early as 230,000 years ago. These creatures hunted large animals, made fires, and wore clothing. About 30,000 years ago, Neanderthals disappeared. Even today, no one has any clue about how this strange extinction occurred.

Click below to see a picture of a Neanderthal: http://www.physorg.com/newman/gfx/news/2006/neanderthalers.jpg

There are other hominids that we know humans did NOT evolve from. These hominids had large bodies and huge teeth and jaws. They also had a unique skull structure and smaller brains. These types of hominids lived in tropical forests and most likely ate tough plant material, like roots. If you were to have ever seen this kind of hominid you would know that this isn’t where humans evolved from.

EARLY and MODERN HUMANS

Only 30,000 years ago two new types of hominids may have lived in the same place at the same time. Scientists think that humans may have evolved from one of the two new types of hominids. The difference these two hominids and other hominids, was that their brains were larger, they made advanced tools, clothing, and even art!

The modern humans are classified as being the species Homo sapiens. The earliest one of these species existed in Africa 100,000 to 160,000 years ago. The group didn’t migrate out of Africa until sometime between 40,000 and 100,000 years ago! The difference between Neanderthals and Homo sapiens is that Homo sapiens have smaller and flatter faces, and have a more rounded skull. Today, the only kind of hominid that still exists is the Homo sapiens.

Click below to see a picture of the early Homo sapiens: http://laelaps.files.wordpress.com/2007/08/progress3.jpg

Bibliography:

Cells, Heredity, and Classification. Holt Science and Technology series. Holt, Rinhart, and Winston. 2007. Pictures: http://www.bfro.net/REF/THEORIES/MELD/evolve1.gif http://library.thinkquest.org/26157/austrman.jpg http://humanisthall.net/HomoErectus1.jpg http://www.physorg.com/newman/gfx/news/2006/neanderthalers.jpg http://laelaps.files.wordpress.com/2007/08/progress3.jpg Timeline: http://web.mit.edu/ealba/www/hominidtimeline.jpg