PrimateEvolution


 * [|Primate Evolution] **

__ What You’ll Learn __ · You will compare and contrast primates and their adaptations · You will analyze the evidence for the ancestry of humans __ Vocabulary __ · ** [|Speciation] ** · [|**Primate**] · ** OpposableThumb ** · ** [|Anthropoid] ** · ** [|Prehensile Tail] ** · ** [|Binocular Vision] ** [|Similarity between primates] is evidence of a shared evolutionary history. Biologists classify primates into two different groups. These are [|Haplorhines] and [|Strepsirrhines]. Haplorhines are a group that includes **[|anthropoids] **, the human-like primates. They have more complex brains than Strepsirrhines. Anthropoids also have larger and different skeletal features. There are old world monkeys and new world monkeys. Old world monkeys are usually bigger. New world monkeys have a long [|prehensile tail]. This means that they can grab things. Humanoids are classified as apes or humans. Apes include Orangutans, Chimpanzees, Gibbons, and Gorillas. Gorillas and humans have the largest brains of all primates. Social interactions are evidence for this. __ New Vocabulary __ · [|Hominoid] · [|Bipedal] · [|Hominid] · [|Australopithecine] · [|Neanderthal] · [|Cro-Magnon] Between 5 and 8 million years ago in Africa, an ancestral population to chimps and humans split into 2 lines; 1 line evolved into chimps, the other into humans. These 2 lines are called **[|hominoids] **. Hominoids are primates that can walk on two legs. This split happened because some primates were forced out of the trees to find food on the ground. It was helpful for them to be **[|bipedal] .** Bipedal means that they can walk on two legs. [|Hominids] are bipedal primates that include modern humans and their direct ancestors. An **[|australopithecine] **is an early hominid that had ape like and human like characteristics. Fossils support the idea the humans were bipedal before their large brain evolved. Early members of the genus Homo made stone tools. In 1964 fossils of the //Homo habilis// were found near small stone tools. Their skulls were very similar to humans. //Homo habilis// literally means “handy human”. They existed about 2 million years ago. 1.5 million years ago, //Homo erectus// came to be. //Homo erectus// means “upright human.” They had a slightly more human like face. About 500 thousand years ago //Homo sapiens// appeared in Europe, Africa, The Middle East, and Asia. These had larger brain cases and smaller teeth. A well known homo species was the **[|Neanderthals] .**
 * __ Section 1 __**
 * __ What is a Primate? __**
 * [|Primates] ** are a group of mammals that includes [|Lemurs], [|monkeys], [|apes], [|Humans]and . The majority of Primates live in trees. All primates have flexible shoulder and hip joints. Primate hands are unique among [|mammals]. They have nails and flexible joints. They also have **[|opposable thumbs] ,** thumbs that can cross the palms to meet the other fingertips. Try the lab at the end of this chapter to see how useful opposable thumbs can be. They enable grasping. Primates have a highly developed type of vision called[| binocular vision]**.** Their eyes face forward so that they can see an object from two view points. This helps with [|depth perception]. Primates also have [|color vision].
 * __ Primate Origins __**
 * __ Human Like Primates Evolve __**
 * __ Section 2 __**
 * __ Hominids __**
 * __ The Emergence of Modern Humans __**

The Neanderthals live about 50 thousand years ago. Their brains were at least as large as modern humans. Neanderthals didn’t evolve into modern humans. Instead, about 35 thousand years ago a species called **[|Cro-Ma][|Cro-Magnon][|gnons] ** came to be and evolved into modern humans. Neanderthals did not evolve into Cro-Magnons. This means that Neanderthals are a sister species of //Homo sapiens//.

This activity will show the usefulness of primate thumbs. 1. Loosely wrap your dominant hand with tape so that your thumb points in the same direction as your fingers. 2. Try to pick up a pen and write a sentence. 3. Pick up your text book and hand it to another student. 4. Throw a ball into a trash can that is right next to you. 5. Try these again, now with your hand unwrapped. 1. Compare the effectiveness of your hand with and without your thumb. 2. Why are opposable thumbs important for primates?
 * __ Activity __**
 * __ Procedure: __**
 * __ Analysis __**

__ Quiz __

Follow the link and take a quiz to see how much you remember: []