EVOLUTION OF MAN

Evolution of Man

Evolution of Man

Introduction

The scientific name for humans is Homo sapiens, belonging to the domain Eukarya, kingdom Animalia, phylum Chordata, class Mammalia, order Primates, and family Hominidae. Two suborders of primates include Strepsirrhini and Haplorrhini. Streptsirrhini includes the mostly arboreal, wet-nosed lemurs, aye-aye, lorises, pottos, and bush babies. Haplorrhini consists of the dry-nosed tarsiers, marmosets, New and Old World monkeys, gibbons, gorillas, chimpanzees, orangutans, and humans (Templeton, 2009). The family Hominidae has four living genera and five species: Gorilla, which contains one species; Pan, which contains two species of chimpanzees; Pongo, which contains one species of orangutan; and Homo, which contains one species, sapiens (Lewin, 2005). This paper presents an analysis of evolution of man from the historical time to contemporary age.

Discussion

In 1863 the British biologist Thomas Huxley described many similarities between humans and apes in his book Evidence As to Man's Place in Nature. Then in 1871 Charles Darwin published The Descent of Man and Selection in Relation to Sex, another seminal text that purported human beings shared a common ancestor with apes. Around 70 million years, mammals developed from the different types of monkeys called primates. The first primates were small animals, nocturnal, living in the trees (Bolsche, 2010). Over time, some of them changed their habits and physical characteristics. Like apes, monkeys, lemurs, and tarsiers, humans are mammals with appendages for grasping on all four limbs, fingernails in place of claws, enlarged cerebral hemispheres, eyes that point forward, and binocular vision with developed depth perception (Lewin, 2005).

Primates Ancestors

Ancestors of the first primates were small mammals that had large eyes, sharp teeth, and ate insects. The earliest known undoubted primate fossils are 55 million years old. The development of hands and feet that could grasp allowed these earliest primates to hang on branches, cling to their mothers, and seize food. Their ability to capture food efficiently and to escape predators quickly evolved along with larger brains, in combination with their agility (Bolsche, 2010). Primates are also characterized by larger cerebral hemispheres and short jaws, and they exhibit complex social behavior and the ability to care for their young.

The anthropoids can be further subdivided into two groups: Platyrrhini, which includes the New World monkeys, and Catarrhini, including the Old World monkeys, apes, and humans (Bolsche, 2010). From a common ancestral primate, the lemurs, lorises, and pottos diverged between 50 and 60 million years ago, and then the anthropoids diverged from what became the tarsiers shortly after that. Approximately 36 million years ago, many primate species became diurnal, meaning they were active and fed during the daytime, in contrast to their ancestors, which were mostly nocturnal, active at night (Templeton, 2009).

Human Evolution and Ancestral Species

One of two misconceptions about human origins is that humans evolved from chimpanzees. Humans and chimpanzees share a common evolutionary ancestor, whose descendents diverged and evolved alongside one another. The other major misconception is that humans represent the pinnacle of a series of hominid ancestors. The term hominid means proto-humans and humans, but its meaning is evolving to encompass other apes such as gorillas and orangutans. Many hominids that lived between 4 and 2 million years ago were already bipedal and ...