Locomotor Patterns

a). Lemurs are found only in the tropical areas of the island of Madagascar and the Comoro Islands, primarily in the treetops. As herbivores, lemurs are found eating the forest's plants. Some lemurs, eat flowers, seeds, leaves. Omnivore lemurs, such as the mouse lemur, eat insects, eggs, lizards, as well as plants.

b). Lemurs locomotor pattern is jumping from tree to tree, branch to branch, using their long tails to keep balance. Unlike their other primate relatives, lemurs don't use their tails to grip branches, instead they use their arms and legs and travel the treetops.

c). Lemur's environment have influenced their locomotor adaptation. Because they are usually traveling the treetops quickly, their arms and legs have adapted to the swift movements. Their tails have adapted in a similar way as well; to give balance as they span the rain-forests instead of being used as an extra limb like their close primate relatives.

a). Spider Monkeys are found in the tropical rain forests of South, and Central America as well as Mexico. They find their food primarily in the treetops, eating nuts, spiders, bird eggs, fruits and leaves. Spider monkeys are pretty noisy creatures; they yell and shake trees when there is danger around such as margay cats and even humans.

b). Spider monkeys locomotor pattern is swinging using all five's; arms, legs and their tail! Their elongated fingers and abbreviated thumb helps swing through branches. Their prehensile tails grip branches to allow them a graceful journey through the rain-forest's treetops.

c). The Spider monkey's environment has significantly  influenced their locomotor adaptation. Their prehensile tails are a handy adaptation for eating purposes; hanging from their tails allows them to gather food with both hands. The spider monkeys ability to grip with their fingers and thumbs allow them to get out of danger swiftly and allows them to vigorously shake the branches to scare away prey.

a). Baboons prefer to live in the savanna and other dry climates, however, few are found in the tropical rain-forests. They eat a variety of food. For example, fruits, grasses, roots seeds, small birds and rodents. Sometimes, baboons act as pests for some farmers because they attack their livestock such as sheep and also eat their crops. They spend most of their time on ground but do sleep in trees.

b). Baboons locomotor pattern is walking quadrupedally, meaning on all fours. Because they are semi-terrestrial they stay on the ground during the day but also climb trees to sleep at night. Baboons do not have prehensile tails because it is not needed as much as other primates.

c). Baboons environment plays an important part in shaping their locomotor patters. Unlike its tropical primate relatives, the baboon doesn't have a prehensile tail to use as an extra limb. What for? Those limb-like tails are primarily used for grasping branches to move from treetop to treetop. The baboon, on the other hand, stays on ground sitting upon rocks as well as sitting or sleeping on rough branches in trees.

a). Gibbons are known as lesser apes, due to their small stature. They are primarily found in the tropical and subtropical rain-forests of the South, East and Southeast Asia. As omnivores, gibbons eat flowers, fruits, leaves, insects, spiders, bird eggs and small birds. Gibbons spend most of their lives in trees, and because of their great skill of mobility in the dense treetops, most predators can not catch them.

b). Gibbons locomotor pattern includes brachiating, traveling from tree to tree by swinging under branches with hand over hand motion. Sometimes, gibbons walk upright, bipedally (on 2 feet), on the tree branches. When they are walking on the branches high in the rain-forests, they stretch their arms out to keep balance, like a tightrope walker. The most common locomotion, however, is brachiation, in which they spend 90% of the time doing.

c). The gibbons environment influences it's locomotor patterns.Their long arms, strong shoulders and lightweight have been adapted for means of traveling, which allows the gibbons to spend most of their lives swinging from branch to branch or walking on branches. The gibbons find all their food supply high on the treetops so there is no reason for them to go on ground. When they are on ground, they have the ability to walk upright, which is an adaptation for outrunning predators.

a). Chimpanzees live in social communities found in  African rain-forests, grasslands, and woodlands. They are usually vegetarians, usually eating fruits, plants, and leaves.However, sometimes male chimpanzees consume insects, eggs and meat. Chimpanzees are very intelligent, pleasant and peaceful animals.

b). The chimpanzee's locomotor pattern is mostly walking quadrupedally as well as walking upright. While walking on all fours, the chimpanzee is also called a knuckle walkers, like gorillas. The chimpanzee also has the ability to swing from tree to tree, where they do most of their eating and sleeping.

c). The chimpanzees locomotion has been greatly affected by its environment. Whether they are walking in groups quadrupedally, or swinging from branch to branch, their locomotor ability is always adapting to their needs. These interchangable traits are constantly at work to the chimpanzees advantage.

I believe that the environments plays such a significant role in influencing physical and behavioral traits . All the primates studied are so alike. However their environmental stresses causes them to physically look different from one another as well as act quite differently from each other as well. Some primates have long arms and strong tails to brachiate and even eat at the same time. On the other hand, some primates lack these prehensile tails because its not necessary where they live. The primates adapted how to walk, swing or jump all because of their differing environments. I think that environments play an enormous role in how organisms adapt their common physical and behavioral traits.

Homologies and Analogies

Homologous traits are those that are shared between two different species that have a common ancestor that possessed those traits and then passed it on to the next generations. Two different species that share a homologous trait are the beaver and the elephant.

Beavers are known as one of the largest rodents. As herbivores, they prefer to eat leaves, bark, roots, and aquatic plants. Beavers are famous for re engineering landscapes and transforming unsuitable habitats by building dams. 

Elephants are the largest land dwelling mammal on Earth! Like the beaver, elephants are also herbivores. They like to eat grasses, bamboos, leaves, bark roots, bananas and sugarcane; eating about 300-400 pounds a day.

One homologous trait that both the beaver and the elephant share is that they both have incisor teeth that have been adapted to for different roles.  For example, the beaver uses its strong, chomping, incisor teeth to fell and gnaw through trees.  With their powerful jaws and strong teeth they create dams, massive log, branch and mud structures.  Elephants, on the other hand, use their elongated incisors, called tusks, for larger tasks which include: digging, stripping bark, moving obstacles out of the way, defense, and even attracting mates.

 With close examination, both are a modification of the basic incisor. With time, evolution adapted these animals' incisors to perform different functions. These homologous traits were inherited from a common ancestor who, most likely, had incisor teeth. I think the Moeritherium was that common ancestor. Its teeth suggest that it was a herbivore that ate freshwater plant and dwelled in swamps and rivers. Fossils showed the beginnings of the enlarged incisors (tusks) but no signs of trunks.


Analogous traits are not the result of a common genetic history, but are due to a common environmental pressure that caused both species to develop a similar adaptation to that stress. Two different species that share an analogous trait are the flying squirrel and the sugar glider.

The flying squirrel, found in North America and Asia, are small tree-dwelling creatures with fragile bones. They have large black eyes and round ears. They have soft brown/gray fur with white bellies. The flying squirrels possess a patagium, a flight membrane that extends between their hands and feet. However, these are NOT wings, more like sails, the patagium allows the flying squirrel to glide over 100 ft.


The sugar glider, found in Australia,  is much like the flying squirrels. They have almost the same color fur as well as the fact that they are tree dwelling as well. They are active in the night while they hunt for insects and small vertebrates. Sugar gliders are also named for their sweet tooth and their ability to glide through the air like flying squirrels.


One analogous trait that the flying squirrel and the sugar glider share are their unique ability to glide to treetop to treetop as well as their similar look. However these creatures do have differences; they are found on opposite of the world, sugar gliders is a marsupial and carries its babies in a pouch, whereas the flying squirrel has larger babies and is from the placentals. By studying there genes and other traits, scientists have come to the conclusion that they are probably not that closely related and they have similar features, such as the patagium due to there environmental stresses of getting from one treetop to another.

Alternative Codon Code

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Malthus the Mentor

Thomas Malthus

(1766-1835)

Thomas Malthus played the most positive influence over Darwin's development of his theory of Natural selection. Malthus's An Essay on Principle of Population was inspiration to Charles Darwin's discovery of natural selection.

Malthus's contribution to the scientific community was his argument in which limits should be placed on population sizes because eventually food supplies and other important resources will run out. An example of his hypothesis being tested is the current human population approaching 7 billion. Thomas Malthus also inspired Charles Darwin's theory of natural selection. Darwin stated in his autobiography (1876), "In October 1838, that is, fifteen months after I had begun my systematic inquiry, I happened to read for amusement Malthus on Population, and being well prepared to appreciate the struggle for existence which everywhere goes on from long- continued observation of the habits of animals and plants, it at once struck me that under these circumstances favorable variations would tend to be preserved, and unfavorable ones to be destroyed. The results of this would be the formation of a new species. Here, then I had at last got a theory by which to work" http://www.ucmp.berkeley.edu/history/malthus.html.

Although Malthus had no interests in species change, he did argue limits to human population. His major point in his essay was "that in nature animal populations increase in numbers when resources are plentiful and/or there aren't many predators" (pg. 34). The points most directly affected by Malthus's work are:

1. All organisms have the potential of reproducing exponentially.
• In Malthus's An essay on the Principle of Population, he explains that for a population to increase, it relies on the the amount of resources available. All organisms do in fact have the potential of reproducing exponentially as long as the food supply remains stable.
2. What is preventing organisms from reproducing at their potential?
• Malthus believed that humans could produce more food to lower the amount of restraints on population sizes. However, Malthus also believed that "the lack of resources would always be a constant source of misery and famine for humankind if our numbers continued to increase" (pg. 34). In this case, the lack of resources would soon be preventing humans from reproducing to our full potential.
3. Resources are limited.
• The most important point Malthus makes is the fact that when the population is limited due to a lack of resources available, there will be a continuous race for those valuable resources. This will be the basis of Charles Darwin's theory of natural selection. Survival of the fittest.

In my opinion, Charles Darwin might have eventually developed his theory on natural selection without the help of Thomas Malthus because he was studying by himself when he found thirteen different finches, all resembling one another, however, slightly adapted to the different environments they were found. However, I also believe that if it weren't for Thomas Malthus's An essay on the Principle of Population,  there would not be a basic foundation for Darwin to form his hypothesis upon.. With this being stated,  Thomas Malthus essays and work played a significant role in influencing Charles Darwin's theory of natural selection.

The attitude of the church, during the 1820's,  viewed  evolution, theories, and scientists as suspicious and associated them with atheism and socialism. The fear that if these ideas were widely popular "the church would crash, the moral fabric of society would be torn apart, and civilized man would return to savagery" (pg. 34). Darwin, being cross to the idea of religion, ended up studying theology. After his graduation Darwin voyaged the world. While in the Galapagos Islands, he studied a species of finches which leads to the publication of his book On the Origin of Species. This will forever change the way we perceive the natural world.