Wednesday, May 7, 2014

It's All About Teeth!

There are five categories of primates: Lemurs, Spider Monkey, Baboon, Gibbon, and Chimpanzee. For each species, the dentition pattern will vary. 

Lemur:
Lemur's tend to live in areas with trees for them to climb and hide in. Unlike their past relatives, lemurs do not posses the ability to hang by their tails. They travel mainly in groups and travel from treetop to treetop.
For the Lemur, they use their teeth for food and also for grooming themselves. They have a “tooth comb”, which consists of the canines and incisors facing outward instead of up. This aids in eating fruit, bark, flowers and other essential parts of their diet.

Spider Monkey:
Spider monkeys are known for having very long limbs and living in the higher parts of rain forests. To travel from tree to tree, they swing by their arms and use their tails to help maintain their balance. 
For the Spider Monkey, their diet mainly consists of fruit and leaves. In order to be able to survive, the spider monkeys have to have a set of teeth that allows them to eat. Their mouth is split into four quadrants, each containing 3 premolars, 2 incisors, 1 canine, and 3 molars. Over time, the Spider Monkey’s teeth have evolved to accommodate the food they ingest.

Baboon:
Baboons can mainly be found in dry deserts and in the jungle. They are larger than most monkeys so climbing trees does not come easily to them. Only if a baboon was in trouble would it climb a tree. 
For the Baboon, they are mainly vegetarian but will eat meat if it has been recently killed. If a baboon was to eat meat, it would most likely be a rabbit or small mammal, due to the dry areas where they inhabit. So, to accommodate their diet, baboons have crowned canines which increasingly get larger as you move to the back of their mouth. Also, baboons show their dominance over others by often flashing their teeth, trying to scare the other monkey or monkeys.

Gibbons:
Gibbons, like their fellow primates the spider monkey and lemur, tend to inhabit trees. They leap from tree to tree and are very acrobatic. They thrive in tropical rain forests and are considered to be one of the most agile primates around. 
Gibbons are similar to baboon with having canines. But because gibbons will eat meat more often than a baboon will, the upper and lower jaws contain crowned canines. Also like baboons, gibbons will show dominance over others by flashing their teeth and trying to intimidate their fellow primates.

Chimpanzee:
 
Chimpanzees are commonly found in Africa and rain forests. They love to hang out in trees but can also survive living on the land. These are the most popular type of monkey and are closely linked to humans.
1.      Finally, for chimpanzees, they are usually only seen eating vegetation provided to them from their surroundings. But there is evidence that they will eat the occasional small animal. The dentition pattern of the spider monkey is nearly identical with the chimpanzee, with the chimpanzee having 2 premolars instead of 3 like the spider monkey.

Summary: 
There are many characteristics that can be seen in each species. Much of their dentition patterns are similar, majority of the teeth are used to eat vegetation and plants that are found in each species surroundings. Certain species also have canines to tear into flesh of small mammals that they may eat. I had no idea that monkeys would even eat animals, I was under the impression that they all are vegetarian. I was proven wrong!

2 comments:

  1. Good images.

    Good description of the dentition. How does the tooth comb help eat? Does it have another function? Can you explain the structure of the other teeth aside from the tooth comb, in terms of how it helps with eating?

    Can you give me the source you used when saying that lemurs lost their prehensile tail trait? This is a trait unique to New World Monkeys and was unlikely present until the rise of those primates in South America.

    Why do you discuss the limb length in spider monkeys? Keep in mind that the post should focus on your specified trait, extending into other traits only if they help to explain dental structures and adaptations to the environment.

    Specifically how is the structure of the spider monkey dentition adaptive to it's environment?

    RE: baboons -- "So, to accommodate their diet, baboons have crowned canines which increasingly get larger as you move to the back of their mouth."

    You are on the right track here, but make sure your vocabulary is accurate. Like all primates, baboons only have one canine per quadrant, so the teeth you are highlighting are the premolars and molars and they do get quite large, not just for meat but also for tougher plant material in the dry savannah. Not a lot of soft, squishy fruit out there. Good job also mentioning the use of defense.

    Gibbons are actually mostly frugivorous, with the majority of it's diet being plant material. It does eat a small amount of birds, eggs and insects, but is not a heavy meat-eater, certainly less than a baboon. So defense is probably the primary function of the canines.

    I would have liked to have seen more connections made with the chimpanzee between diet and tooth structure.

    You can actually divide up these primates into two groups, two that have 3 pre-molars (lemurs/spider monkeys) and three that have two premolars (baboons/gibbons/chimps). Can you explain this pattern? Why would old world monkeys and apes have lost that premolar?

    You did a better job in your summary of trying to connect form with function in the dentition. Better, clearer connections.

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  2. Hello, Kayleigh,
    I want to start off by saying I enjoyed reading your blog post. I also wanted to say I found it interesting that baboons and gibbons act in a similar manner by showing off their teeth when trying to scare off another monkey. It is also interesting that baboons and gibbons are quite similar primates. In addition to your wonderful blog post, I liked your choice in pictures!
    Keep up the great work! (:

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