The Appearance of New Species - Assignment Example

What mechanisms lead to the appearance of new species? Illustrate your answer with an example. (3 pts) Natural speciation: appearance of new specie occurs over the course of evolution. For instance, a marine fish known as three-spined stickleback goes through natural speciation when placed in freshwater colonies. The resulting species have major structural alterations from the original species. Evolution by natural selection: offsprings produced by natural selections emerge with high quality traits which are easily adapted to the environment such that the death of the parents as a result of challenges in the environment result in offsprings who are readily adapted to survive well in such situation. For instance, the DNA of humans. 2. A) Describe and compare cladogenesis and anagenesis. (2 pts) Cladogenesis is a form of splitting where the main branch and its sub branches form an evolutionary strategy which is adaptable and eventually leads to formation of high quality range of sister organisms. On the other hand, anagenesis is a gradual evolution which leads to overall replacement of a species by its novel form. B) How does the phylogenetic tree that uses “prosimian vs. anthropoid” differ from the cladogram that differentiates “strepsirhine versus haplorhine”. (1 points) A phylogenetic tree that uses “prosimian vs. anthropoid” contains prosimian while the cladogram that differentiates “strepsirhine versus haplorhine” views prosimian as an outdated concept. 3. A) On a separate sheet make a cladogram by hand for primates that includes groups 1-g and the tarsier (you will probably have to turn the page to fit all the groups). B) Then List 3 shared derived traits (if that many exist) that cladists use to define the common ancestor ( total 12 points, 3 for cladogram 9 for traits) 270. a) all primates – i. Opposable thumb adopted for arboreal lifestyle. ii. Enlarged brain size. iii. Reduces number of teeth b) strepsirhines – i. They have a wet nose otherwise known as rhinarium. ii. They have huge olfactory lobes adapted for smell. iii. Each foot has a grooming claw on the second toe. c) haplorhines - i. Their upper lip is not linked to their nose directly. ii. They have a large brain to body ratio. iii. They possess a postorbital plate. d) tarsier - i. They have a huge visual cortex used for processing information. ii. They lack the reflective layer (tapetum) in their eyes. iii. They have a scaly tail. e) anthropoids – i. Their females have a tendency of twinning. ii. Their dentition contains fewer molar iii. They are also polyandrous in nature. f) platyrrhines - i. They are flat nosed. ii. They are mostly terrestrial. iii. Their niche is narrow. g) catarrhini i. They possess sexual dimorphism traits. ii. They live in social groups. iii. Their nostrils face downwards. h) cercopithecoidea i. They possess long rostrum and their skull is deeply corrugated. ii. They are diurnal. iii. Their fur is neither wool like nor silky. i) hominoidea – i. They have no external tail. ii. Possess learnt behavior patterns. iii. Their dentition has a Y-5 pattern. 4. Give an example of one primate species that belongs to each of the following clades, then explain where it leaves (Australia etc…), and something interesting about it (6 points) Ape (hominoidea): Orangutans a primate species of the apes. They are found in Asia. Orangutans have a manifested sexual dimorphism. lemur : Madame Berthes mouse lemur is a primate species of lemur which are found in Madagascar. Lemur species were carried to Madagascar by rafting on mats of vegetation by ocean currents. loris primates : pottos, galagos and angwantibos are primate species of loris primates. They are found in Africa. They only hunt easy Prey such as eggs, insects and small birds. Tarsier : Tarsier bancanus is a primate species tarsier. They live in southern Philippines. Tarsiers are adapted to leaping with their legs and muscles comprising approximately a quarter of the total body weight. Platyrrhine: species of Platyrrhine include Chiropotes satanas and Pithecia pithecia. They are found in Central and South American rain forests. The species engage in polyandrous mating systems. Cercopithecoidea: species in this group include talapoins, macaques, surilis and geunons. They are found in several places including Southeast Asia, Africa and India. Some species are terrestrial while others are arboreal. Ape (hominoidea): Orangutans a primate species of the apes. They are found in Asia. Orangutans have a manifested sexual dimorphism. 5. A) What advantages and disadvantages do primates gain from living in groups? (4 pts) Advantages I. Primates are able to cooperate during food collection such as hunting so that they are able to track game together. II. Living in group enables primate to conserve their warmth especially during the nights. III. It enables primates to share information on matters such as where to locate food, roots of fruits. IV. Living in groups enables primates’ protection from their predictors. V. Defense of their resources such as fruits, water and other important resources from attacks by other animals. Disadvantages I. Hunting together leads to sharing of game among the hunters II. They are easily noted by their predictors. III. Living together intensifies internal conflicts. IV. Competition for resources such as food, space and mates. B) Primates have evolved a number of different social organizations, in your own words define and discuss each of the following social categories and then for each category give an example of one primate species (different from those used in your answers above) whose social organization falls into that category and discuss something interesting about that species social life. (21 points) Noyau: Noyau is seen in orangutans and they depict promiscuous mating patterns. These primates do not live in groups as they live in isolation. The home ranges where the primates live are intersecting and both females and males do not live together. There are no set boundaries on the ranges. While females have single home range, males have a relatively huge range that covers several ranges occupied by the females. Monogamy: An example of a primate who portrays monogamous mating patterns are the gibbons. In this case, there is only one pair and their respective offsprings. Mates engage with only one primate all their lives, there is no promiscuity. Polyandry: primates who practice polyandrous mating include Goeldis Marmoset. Polyandry involves one female primate taking multiple males. Every territory exhibiting mating aspects involves a single female but with many males. The system of mating is promiscuous in nature on the part of the females. Multi-male group: Primates who exhibit multi-male feature include Macaques. Each territory has multiple males. Usually, multi-male groups have numerous numbers of both sexes. They exhibit promiscuous mating patterns where they mate with no specific mate. One-male group: leaf-monkey is an example of primates showing mating characteristics of one-male group. This system involves a polygamous mating system where a male leaf- monkey mates with several females. The remaining males in the territory form a heard of bachelors who invade the old males from time to time and take away their power and their women. Fission-fusion society: this type of social organization is not very common in primate but it can be seen in spider monkeys, bonobos and chimpanzees. Here, a territory is shared by a group of of primates. The group members are hospitable to one another. They work together and protect the group members from any harm coming from non-members of the group. During the day, they do not walk along together as they divide themselves in smaller groups which split and join at regularly. Hamadryas : primates depicting this type of social organization in the baboons. This system has several levels presented in a complex hierarchy. The simplest unit is a one-male unit which is complemented by females. The small units then combine into larger units known as the clans. The clans then combine with each other to form troops during the night but at night, they move back into their respective clans. 6. Based on what we know about the cognitive capabilities of chimps and bonobos (remember the movie “Can chimps talk” including the Kansi experiments by Sue Savage-Rumbaugh, and the M & M experiments with Robbi by Sarah Boysen) - what cognitive and linguistics capabilities would have been present in the last common ancestor of chimps, bonobos and humans? (5 pts) The last common ancestor of chimpanzees, bonobos and humans showed signs of increased brain size in terms of organization and operations. The brain of the last common ancestor can be traced to have about 300–400 g which depicted several unique cognitive phylogenetic specializations of progress, functional organization, and biological function. The significant growth of the brain was also responsible for increased linguistic abilities traced to the communication of the last common ancestors. 7) In her book Goodall discusses how different kinds of mothers and approaches to mothering affect the personality and success of their offspring. Provide three examples from the book about specific mothers (hint – initials F vs P) and their offspring which support Goodall’s position. (12 points). In chimpanzees at Gombe, parental care is the obligation of the mother. A mother oversees he survival and emotional health of their infants. Goodall focuses on three women who portray different mothering strategies with their children. The first women presented are Flo and Passion and how they display their parenting strategies to their daughters Fifi and Pom (Goodall, 1986, p. 106). Goodall notes that Flo and Passion daughters have taken different paths in life as opposed to their parents. Parenting can also be portrayed on how these females demonstrate parenting of their sons. Flo’s parenting abilities are seen as attractive in the way she has the influence over other males, sons and mates. This focuses on how Flo assists his son Figan in achieving Alpha male status in the community. Passion demonstrates weird parenting skills. Passion’s parenting skills are demonstrated in her daughter Pom (Goodall, 1986, p. 137). Both of them are involved in attacking Gilka’s and Melissa’s infants. Unlike Passion, Flo intensifies her concerns and investments in her offsprings. She is very watchful with her offsprings and spends a lot of time overseeing them (Goodall, 1986, p. 107). This is demonstrated by the way she treats her offsprings with affection, compassion, soothing and kissing them to give them reassurance and subdue their fears (Goodall, 1986, p. 242) . Another female ho demonstrates good parenting skills is Melissa. She is Goblin’s mother. She is very understanding and motivates her son to achieve alpha status. 8) A) In several places in her book Goodall discusses the sexual relationships between male and female chimpanzees, and provides several “coming of age” stories. Describe what you learned about the relationship between male and female chimps and how different males approach females and some manage to ensure only they reproduce with them. As a human, how do you feel about the way male chimpanzees treat the females? (12 points) According to Goodall, (1986, p. 77), male chimpanzees are said to have come of age when they reach adolescents as from nine years old. As form 16 years and older, male chimpanzees are capable of reproduction. Mating and reproduction take places any time of the year. Childbirth has no specific season in the year too. However, females are seen to demonstrate seasonality in the group in terms of the number of estrous females. The availability of estrous females in the group is determined by the availability of food because they require a lot of food during the ovulation period. Reproductive behavior of chimpanzees is mostly promiscuous in nature. During estrus, females mate with numerous number of males at every opportunity they get. They are not defined by a single male as in monogamous relationships. Majority of female copulation take place during a time of maximal tumescence which is marked by a 10-day period. Male chimpanzees may use some strategies to restrict their desired females form mating with other males but them. This is known as restrictive mating. There is also consortship mating. In this case, pair of adult leaves the community and go for mating in another place. This can last for days or even months. Other females may leave the community and go to secretly mate with neighboring males. Females maintain multiple strategies which enable them to maintain an expanded pool of mates from where they can choose from. This also enables the females to increase the chances of male’s reproductive achievements. B) Is there anything odd sexually about the relationship between baboons and chimpanzees? (2 point) Baboons and chimpanzees are very aggressive sexually. They have the tendency of forcing females to yield into their demands in case they are not paid attention to. Female chimpanzees too can be seen to maintain repeated sexual cycles with different sexual partners. 9) Describe the dark times at Gombe during the early 70s including the “war”, Passion’s weirdness, Gilka and her fate, and the human drama (10 points). The observation of animals in Gombe national park Tanzania provides more knowledge on the behavior of chimpanzees such as their social relationships. Male chimpanzees engage in intercommunity violence and struggle so as to achieve alpha male status. This is also done by portraying intimate aspects of their individual lives. ‘War’ highlights aggression and violence. The male chimpanzees compete strongly with all their might for fertile females. They mostly use violence and brutality to conquer unruly females so that they can accede to their sexual conquests. Passion is a weird female chimpanzee with cannibalistic traits who engages in murderous attacks to end the lives of other chimpanzee’s infants. She kills two of Gilka’s infants which leave her childless. Mellisa is yet another chimpanzee who losses one of her infant to passion but is able to produce surviving offspring as she lives up to adulthood unlike Gilka. Gilka is a female chimpanzee who was low- ranking and was plagued by a calamity which persisted her whole life. She lost two of her infants when they were attacked by Passsion and Pom. Gilka is not able to produce more children which will survive her. 10) How did Figan and Goblin achieve alpha male status in their group? (10 points) Male Chimpanzees from high ranking lineages in Gombe are bale to achieve alpha male status with the help of their mothers and brothers. Figan is Flo’s offspring. He achieves alpha male status dramatically with the assistance of his brother Faben at the tender age of eight years. Figan is able to employ strategic tactics which enable him to uphold this status despite the constant challenges which are advanced by his rival, Everend. Goblin is Melissa’s son. Goblin is highly obsessed with the idea of becoming an alpha male and is motivated to do so by defeating all odds. The acquisition of alpha male status by chimpanzees is taken as a matter of psychological aspects as opposed to physical build and brute. Although goblin is small-bodied, he is able to dominate Figan. Goblin goes to show that variations in the male chimpanzee’s quest for high ranks in the community an avoiding encounters from others is based on the ability of such chimpanzees to assess intelligently a condition, have the motivation and eventually be willing to invest their energy in displays and fights. Very little emphasis should be placed on the size of the body. Work cited Relethford, John, The human species: An Introduction to Biological Anthropology, McGraw-Hill, New York. 2007. Read More