Comparative Primate (Fourth Post)

Comparative Primate  -  Dentition Patterns

Lemurs (Prosimians/Strepsirhini)

1. "Lemurs live in trees but some large species of them also spend time on the ground. They are only found on the Comoro Islands and Madagascar Islands. They live all over the place rather than in just one particular region. Some Lemurs live in the rain forests but others live in very hot and dry areas. Overgrown forests seem to be the location where the highest number of Lemurs are found."
2. "They have long, curved, rodent-like incisor teeth. The lemur dentition is heterodont (having multiple tooth morphologies). Lemurs are unusual among primates for their rapid dental development. The toothcomb in lemurs normally consists of six teeth (four incisors and two canines). Lemurs are also dentally precocious at birth, and have their full permanent dentition at weaning."
3. "In the toothcomb of most lemurs, the bottom incisors and canine teeth are procumbent (face forward rather than up) and finely spaced, thus providing a tool for either grooming or feeding. While fork-marked lemurs use their relatively long toothcomb to cut through tree bark to induce the flow of tree sap. Indri, the largest living lemurs, have teeth that are perfectly adapted for shearing leaves and crushing seeds. "

Spider Monkey (New World Monkey/Platyrrhini) 

1. Spider monkeys live in the tropical rain forests of Central and South America and occur as far north as Mexico. These monkeys spend most of their time aloft. These New World primates gather in groups of up to two- or three-dozen animals. At night, these groups split up into smaller sleeping parties of a half dozen or fewer. Foraging also occurs in smaller groups, and is usually most intense early in the day. Spider monkeys find food in the treetops and feast on nuts, fruits, leaves, bird eggs, and spiders.
2. Spider monkeys have large incisors and small molars with low rounded cusps.
3. The larger incisors and small molars of the spider monkey reflect the largely frugivorous, mainly fruits, diet.

Baboon (Old World Monkey/Cercopithecidae) 

1. All five different species of baboons live in Africa or Arabia. Baboons generally prefer savanna and other semi-arid habitats, though a few live in tropical forests. They climb trees to sleep, eat, or look out for trouble. They spend much of their time on the ground. Baboons are opportunistic eaters. They eat fruits, grasses, seeds, bark, and roots, but also have a taste for meat. They eat birds, rodents, and even the young of larger mammals, such as antelopes and sheep.
2. They have heavy, powerful jaws with sharp canine teeth. Males can have canine teeth as long as 2 inches.
3. The long canine teeth you see on a male baboon are adaptations for male-male competition; males use these teeth to fight with other males and gain access to females. More commonly, males do not even have to use their teeth: they simply display them to other males in an open-mouthed threat or yawn, which serves as a signal to other males to stay away.

Gibbon (Lesser ape/Hylobatidae) 

1. These acrobatic mammals, endemic to the dense forests of southern Asia, ranging from northeastern India to southern China to Borneo, are perfectly adapted to life in the trees and rarely descend to the ground.
2. They have teeth that are downward in shape. Their teeth also are similar to the great apes, with molars that are bunodont and lack lophs. The upper molars usually have a cingulum, which is sometimes large. The canines are prominent but not sexually dimorphic. 
3. The molars are sharp which can help them for fighting off predators and for food. 

Chimpanzee (Great ape/Hominidae) 

1. Wild chimpanzees are only found in Africa, where they inhabit 22 African countries, from the west coast of the continent to as far east as Tanzania. Chimps live in tropical rainforests of what used to be the equatorial forest belt of Africa. Some chimps are able to move into quite arid areas, such as southwest Tanzania and Senegal, where they are found in secondary forests, open woodlands, bamboo forests, swamp forests, and even open savannah. Chimps seldom venture far away from forests, except when moving from one forest patch to another; They spend considerable time in trees, where they sleep, forage and socialize.
2. Apes (humans included) all have the same dentition pattern. They also have baby teeth, known as their “milk teeth,” that they loose when the adult teeth come in.
   One difference between our dentition is that though non-human apes have canines in the same place as humans, their canines are much larger than ours.
3. "What we know about diet probably doesn’t explain why they would have almost carnivore-sized canines. Since they eat mostly fruit, leaves, and other plant items as well as sometimes small mammal meat. Still, even that small amount of meat wouldn’t be the reason for why non-human apes have such large canines. What other purpose can teeth serve if not to chew up food? Threat. Certainly large canines are quite intimidating, and can serve as a warning to enemies to stay back, or else you could get bit and it’ll hurt!"

In conclusion, each of these primates have similar teeth structures with the large canine's being the outlining pattern. A fruit being a common meal, their teeth have developed to help with seeds and the skin of fruits. As said on the example Primate website, "All primates have essentially the same kinds of specialized mammalian teeth adapted to eating a wide variety of foods." Depending on the environment and the type of food that is available to them, certain teeth are put to better use then others.

Sources:

http://www.lemurworld.com/lemur-habitat/

http://en.wikipedia.org/wiki/Lemur#Dentition

http://animals.nationalgeographic.com/animals/mammals/spider-monkey/

http://en.wikipedia.org/wiki/White-bellied_spider_monkey#Dentition

http://animals.nationalgeographic.com/animals/mammals/baboon/

http://www.imfene.org/misconceptions-about-baboons

http://animals.nationalgeographic.com/animals/mammals/gibbon/

http://www.monkeyworlds.com/gibbon/

http://www.newworldencyclopedia.org/entry/Gibbon

http://www.janegoodall.ca/about-chimp-range-habitat.php

http://www.chimpsanctuarynw.org/blog/2013/07/chimpanzee-teeth/

http://primateevolution.tripod.com/id4.html

http://anthro.palomar.edu/primate/prim_4.htm