Locomotion in Primates

Lemurs (Prosimians/Strepsirhini)

Lemurs are native only to the island of Madagascar and its neighboring Comoro islands. They are mostly arboreal creatures and usually spend their time in the canopies of the rainforest. Most lemurs are awake during the day and asleep at night except for the several few who are nocturnal such as the mouse lemurs and dwarf lemurs.

Their locomotion can vary depending upon the species of lemur but the most common is quadrupedal, with short bouts of bipedalism. They tend to run on branches or leap between them, using their hind legs to push off and landing on either hind legs or on all fours. This allows them to travel easily between trees, which occupy the majority of their habitat.

How we see their locomotion develop was through the climatic extremes of Madagascar, rainforest to the east and dry regions to the west. We see that specific lemurs such as the fork-marked lemurs feed on tree gum, sportive lemurs feed on leaves, and giant mouse lemurs occasionally feed on insect secretions. But lemurs have sometimes been described as being opportunistic omnivores, leading to the need to be in trees. Along with dietary needs trees provided escape from predators along with being able to quickly travel through the trees for food.

http://www.britannica.com/EBchecked/topic/476264/primate/225204/Four-types-of-locomotion           

library.sandiegozoo.org/factsheets/ringtailed_lemur/lemur.htm

Spider Monkey (New World/Platyrrhini)

Spider Monkeys are found mainly in the tropical rain forests of Central and South America, Brazil, and Mexico. They are arboreal creatures and mainly live in evergreen rainforests, semi deciduous and mangrove forests. Spider monkeys like to stay in the upper canopy and rarely ever go to the forest floor.

The majority of the Spider Monkeys locomotion revolves are suspensory and quadrupedal. Suspensory locomotion is seen when they are hanging, climbing, or in some cases gliding through trees. Suspensory locomotion is also seen when they use their tails to climb or grab onto things. While quadrupedal is seen but in some cases when they are running or walking on all fours, which they generally only do when on a stable surface when searching for food.

Since Spider Monkeys mainly live in the upper layers of the rainforest they would require a need for climbing and jumping from tree to tree. And their primary source of food is fruit, leaves, nuts, flowers, and insects; it would make sense that they would evolve towards suspensory and quadrupedal locomotion.

http://www.angrydmonkey.com/different-locomotion-in-spider-monkeys-study.htmlBaboon (Old 

Baboons (World Monkey/Cercopithecidae)

Baboons tend to be ground dwelling and are found in the savannah, open woodlands and hills across Africa. Being mainly omnivores and vegetarians, with the exception of the occasional goat or sheep, they tend to be more hunter-gatherers.

Their locomotion patterns tend to be quadrupedal, walking on all fours and specifically on their digits. This allows them quick movement on level ground. Since baboons are a larger primate and located in the Africa there are not many trees to climb, so it would make sense that they would be quadrapedal due to their available sources of food.

Gibbon (Lesser ape/Hylobatidae)

Gibbons live in the tropical rainforest of Southeast Asia. In the rainforest they tend to live in the treetops. Their locomotion consists mainly of brachiation and bipedalism. Briachiation consists of moving by swinging of their arms as well as the walking on two legs. They are on of the most acrobatic apes being able to practically fly through the treetops. Along with that they are able to walk both on the ground and on branches on only two legs.

Since the gibbons are so fast at gliding through trees virtually no predators are able to catch them. They were able adapted for their food and to get move with alarming rates through the forest. They mainly eat fruits, leaves, flowers, tree bark, and occasionally insects. And though they have the ability to walk on the ground they tend to stay in the trees to avoid predators and to forage for food. 

http://www.enchantedlearning.com/subjects/apes/gibbon/

Chimpanzee (Great ape/Hominidae)

Chimpanzees inhabit about 22 African countries from the west coast to the east as far as Tanzania, but wild populations are only found in Africa. The Chimpanzees live mostly in tropical rainforests, mostly the equatorial forest belt of Africa. Are able to live in both arboreal and terrestrial environments but generally tend to stay near forests.

The Chimpanzees locomotion is quadrupedally on the ground or in trees but also have brachial and bipedal abilities. They can travel either on all fours, on only 2 legs, as well as swing/climb trees. Along with that they have opposable thumbs so they are able to stand and hold things.

These adaptations definitely came from the environment, being as they are able to adjust to many different environments. They survive on fruits, leafs, and insects but do occasionally hunt and have adapted to do so. Creating the need for both the speed of quadrupedalism and the ability to stand and grasp things that comes with bipedalism. And the foraging abilities that comes with braichiality and the ability to climb.

  

http://www.janegoodall.ca/about-chimp-behaviour-diet.php

Conclusion

               In conclusion, i believe environment has a big role to play in the development of physical and behavorial traits. All the different primates had adapted not only to the environment but adapted in such a way that they can avoid predators and collect food. though they all live in different environments they all generally lived in areas with forests or trees, except baboons. Along with that most of the primates shared a similar diet of plants, fruits and occasionally insects--except baboons and chimpanzees who occasionally would hunt. And though they were all different species of primate, being quadrupedal was a general locomotive trait they all shared.