I) Read the below article and answer the questions.
In 1974, Donald Johanson, an archaeologist from Case Western Reserve
University in Cleveland, Ohio, found parts of a skeleton there that dated back 3.2
million years — the oldest hominine bones yet discovered. Johanson nicknamed
the skeleton “Lucy,” because that night, as he and the others in camp celebrated
their discovery, they listened repeatedly to the Beatles’ song “Lucy in the Sky with
Diamonds. ''Lucy was assumed to be female because the bones were of a small
hominin, roughly 3 and a half feet tall. Only about 20 percent of a full skeleton was
found, and most of the skull was missing. Fragments suggest it was small, while the
foot, leg, and pelvis bones showed that Lucy walked upright. This was important
evidence that, in the human line, bipedalism came earlier than brain growth, which
previously had been supposed to come first
a. Use the claim testers - Evidence and Authority and provide justification from
the passage.
b. CLAIM- Chimpanzees are our ancestors. Use any of the claim testers and
provide your justification.
pls i need the ans quick
Answers
Lucy & the Leakeys
Until the 1950s, European scientists believed that Homo sapiens evolved in Europe, or possibly in Asia, about 60,000 years ago. Since then, excavation of fossil bones in East Africa, pioneered by Mary and Louis Leakey, has revealed that Homo sapiens may have emerged in Africa much earlier.
Human origins
Most scientists agree that the human species emerged somewhere in Africa about 200,000 years ago. This understanding is based on fossilized bones and skulls that have been uncovered in East Africa and dated accurately by radiometric dating. These bones and skulls range from 25,000 to 4.4 million years old and show many different stages of human and primate evolution. These fossils have been uncovered by paleoarchaeologists — scientists who study the material remains of the entire human evolutionary line.
Based on the fossil evidence, paleoarchaeologists currently tell the following story: For 99.9 percent of our history, from the time of the first living cell, the human ancestral line was the same as that of chimpanzees. Then, about 5–7 million years ago, a new line split off from the chimpanzee line, and a new group appeared in open savanna rather than in rainforest jungle. The old group in the rainforest continued to evolve, and two of its species remain in existence: the common chimpanzee and the bonobo.
The new group in the savanna evolved over the millennia into several species (how many is not entirely clear, but at least 18 different ones), until only one was left: Homo sapiens. All the species before us back to our common ancestor with chimpanzees are now collectively called “hominines.” (They used to be called “hominids.”)
Try visualizing it like this. Imagine your mother holding hands with her mother, who is holding hands with her mother, and keep going back in time for 5 million years. The final clasping hand would belong to an unknown kind of an ape whose descendants evolved into chimpanzees, bonobos, and, ultimately, your mother. If we count each generation as averaging 14 years, there would be about 360,000 hand-holders in the hominine line. (Thanks to Richard Dawkins, a contemporary English biologist, for this metaphor.)
Paleoarchaeologists debate what names to put on the bones they find. They have to decide which ones ought to be considered a separate species. No central authority determines this, so paleoarchaeologists discuss it and try to reach a consensus. They more or less agree on three main categories of species before Homo sapiens; these are Australopithecus (2–4 million years ago), Homo habilis (1.8–2.5 million years ago), and Homo erectus (2–.4 million years ago). Clearly, some of these species must have overlapped during hominine evolution.
What scientists now know took many years to figure out. The first early human fossil bones were found in Europe — Neanderthals in Germany in 1857 and Cro-Magnon in France in 1868. Java Man was found in Sumatra, Indonesia, in 1894. Most paleoarchaeologists in the 1920s and ’30s felt certain that Homo sapiens must have evolved in Europe, or possibly Asia, since a group of fossils known as Peking Man was found in China in 1923–1927. Africa, widely known then as the “Dark Continent,” was not considered a possibility largely due to racist thinking.
Louis Leakey measures an ancient skull found in Tanzania. © Bettmann/CORBIS
The Leakeys look to Africa
When did anyone start looking in Africa for hominine fossils? One German professor found a Homo sapiens skeleton in 1913 in Tanganyika (now Tanzania), and a professor in South Africa found a child’s skull there in 1924. But archaeologists denied that these bones were significant. The first to make credible finds were an English couple, Louis and Mary Leakey.
Louis Leakey was born and grew up in Kenya, in a tiny mission village nine miles from Nairobi, now the capital of Kenya but then a small village on the railroad to Lake Victoria, the source of the Nile River. Louis’s parents were missionaries from England. They hired English tutors for their children, but mostly Louis spent his childhood hunting and trapping with the local Kikuyu boys. Louis spoke Kikuyu as a native language and went through initiation rites with his Kikuyu peers. At the age of 13 Louis built his own house, as was Kikuyu custom. He also found some relics that he recognized as ancient hand axes, even though they were made of obsidian rather than flint, like the ones in Europe were. World War I prevented Louis from being sent to boarding school in England; he was 16 before he traveled to London to prepare for entrance to Cambridge University to become an