Lemurs (Prosimians/Strepsirhini)
Lemurs live exclusively on Madagascar Island and the nearby Comoro Islands. 80% of species found at Madagascar are found nowhere else in the world. The island consists of tropical rain forests (along the eastern edge) and arid dry forests (western coast).
Lemurs are very diverse group of primates. Most Lemurs are arboreal, however; Ring-tailed lemurs are living semi-terrestrially and 25% of the time they live on the ground. Since lemurs have very diverse groups they come in different shapes and sizes. Some of them have a fairly large body size that requires a large area to obtain food.
There’s only little sexual dimorphism among Lemurs. The Black Lemur (male and female both medium-sized with an overall length of about 38inches and weight 5Lbs) shows sexual dimorphism (male is black and the female is brown with a white underside). Some female Lemurs are larger than the males.
After a big storm, Lemurs have been washed out of Africa and they landed in Madagascar. Male and female differences are not very significant in Lemurs. The fact that they are living in small groups and their Polygynous (many females live with one male) nature of relationship may have plaid a big role in this subject matter. When Lemurs arrived to Madagascar they filled many Ecological niches and didn’t have to compete with monkeys that were living in Madagascar.
Male and Female LemursSpider Monkey (New World Monkey/Platyrrhini)
Spider Monkeys are New World monkeys that are found at Tropical and sub tropical forests of central and South America (preferably peaceful and quiet areas). Spider monkeys eat fruit, insects and also flowers. Spider monkeys have powerful tail that they use as an extra limb. Spider monkeys are among the largest of New World monkeys. They have long legs, arms and tail and this is where the word “spider” for spider monkey comes from.
Sexual dimorphism among Spider monkeys is little. The average weight for wild black spider monkey males is 10.8 kg (23.8 lb) while females weigh 9.66 kg (21.3 lb) on average. The height of male spider monkey averages 557 mm (1.83 ft) while females average 552 mm (1.81 ft)
Just like Lemurs, Spider monkeys are polygynous and this type of life style protects females and limits competition for the male. Since there is only a small competition, male monkey don’t need to adapt huge differences to attract female monkeys. This is why male and female spider monkeys look alike (have only a little sexual dimorphism).
Baboon (Old World Monkey/Cercopithecidae)
Baboons are found in Arabia (Savannas or other arid habitats or tropical rain forests) and Africa. Baboons are omnivores and they mostly eat roots, seeds and grasses. . Baboons range in size from 33 to 82 pounds and average 20 to 40 inches long (tail not included).
Baboons are found in Arabia (Savannas or other arid habitats or tropical rain forests) and Africa. Baboons are omnivores and they mostly eat roots, seeds and grasses. . Baboons range in size from 33 to 82 pounds and average 20 to 40 inches long (tail not included).
Olive Baboon, Yellow Baboon and Gelada Baboon are different types of Baboon.
Sexual Dimorphism example in Yellow Baboons: Adult males and females have longer hair along their flanks compared to the rest of their bodies while males have longer fur at the nape of their necks. Yellow baboons have a prominent brow ridge covered in yellow-gray fur, but the rest of their face appears black and is only finely covered with fur. All baboons are sexually dimorphic. Wild yellow baboon males have an average height of 1200 mm (3.94 ft) and weigh 25.8 kg (56.9 lb) while females measure 976 mm (3.20 ft) and weigh only 11.0 kg (24.3 lb), on average (Altmann et al. 1993). Variation in length and sharpness of canine teeth is also seen among males and females. Male baboons have long, sharp upper canine teeth compared to females. They use their canines in aggressive interactions with other males and when feeding on large vertebrate prey.
male and female BaboonsGibbon (Lesser Ape/Hylobatidae)
The reason why Gibbons are called Lesser Ape is because of their small body size. Gibbons live at the rainforests at Southeast Asia. Being arboreal is an advantage for Gibbons (spend less than 1% of their time on the ground). It also has a survival value for Gibbons by keeping them away from predators. Gibbons branchiate using their long arms and thumb (adaptation).
White-Cheeked Gibbons: found in China and Vietnam.
Sexual Dimorphism: male and female are similar in body size (and also their genitalia is very similar). 18 inches tall and weighs 15 - 20 Lbs. Infants are born beige and within 6months they become black with white cheek patches. When sexual mature, male Gibbons remain black and females return beige again.
Male and Female GibbonChimpanzee (Great ape/Hominidae)
Humans and Chimpanzees share about 95% to 98% same DNA. Chimpanzees are found in 22 countries across a west-east belt in equatorial Africa. chimpanzees live in a wide variety of habitat types (dry savannas, evergreen rainforests, Montane forests, swamp forests, and dry woodland-savanna mosaics). Chimpanzees use sticks, rocks and grass to make tools and use those tools to acquire and eat honey, ants, nuts, and water. Average life span for Chimpanzees is 40 to 45 years.
Humans and Chimpanzees share about 95% to 98% same DNA. Chimpanzees are found in 22 countries across a west-east belt in equatorial Africa. chimpanzees live in a wide variety of habitat types (dry savannas, evergreen rainforests, Montane forests, swamp forests, and dry woodland-savanna mosaics). Chimpanzees use sticks, rocks and grass to make tools and use those tools to acquire and eat honey, ants, nuts, and water. Average life span for Chimpanzees is 40 to 45 years.
Chimpanzees are slightly sexually dimorphic with males, on average, weighing 40 to 60 kg (88.2 to 132 lb) and females, on average, weighing 32 to 47 kg (70.5 to 104 lb). Males and females have an average height of 816 mm (2.68 ft). Male Chimpanzees have less tolerance toward unfamiliar male Chimpanzees. They might see the unfamiliar faces as a mating competition. Chimpanzees are born with pale faces and a white tail tuft (both darken with age). Both males and females have beards and prominent ears. At night, all Chimpanzees build tree nests for safety. Female Chimpanzees have sexual swelling during estrus. Attacks (by lions and Leopards) are the number one reason for mortality among Chimpanzees. Dr. Jane Goodall contributed a lot on what we know about Chimpanzees today.
using tools
Dr. Jane Goodall and ChimpanzeeAfter answering the question and learning more about these 5 primates, I discovered that most of them lack sexual dimorphism. However, Baboons exhibit the greatest sexual dimorphism among the primates. The environment that each of these primates are living has influenced their body size and traits slightly. Some primates are able to swing and climb up the trees easily and they have adapted to tree living style.
2 comments:
Comparing Size and Sexual Dimorphism
Your environmental descriptions and the descriptions of size and dimorphism were excellent. You also made great connections between body size/dimorphism and other factors (like the environment) for the lemurs and spider monkeys.
Unfortunately, you left out that analysis for the baboons, gibbons and chimps. You were on the right track... I would have liked to have seen your answers.
Summary?
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