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SIR CHARLES LYELL & PROF. T. H. HUXLEY
Sir Charles Lyell (1797-1875) was a British geologist. In his Principles
of Geology (3 volumes, 1830-33), Lyell conclusively showed that the earth
was very old and had changed its form slowly, mainly from conditions such as
erosion. Lyell was able to date the ages of rocks by using fossils embedded
in the stone as time indicators. Charles Darwin made use of Lyell's data on
fossils for his theory of evolution. Lyell himself had believed that the
various species of plants and animals had remained unchanged since they were
created. When confronted with Darwin's findings, he admitted "I now realize
I have been looking down the wrong road." He became one of Darwin's
strongest supporters. Lyell was born in Scotland. He studied geology at
Oxford University and traveled on several geological expeditions in Europe
and North America.
But the first and one of the strongest supporters of Darwin's theory was
Thomas Henry Huxley (1825-1895). A British anatomist and physical
anthropologist, Huxley became the foremost advocate of the Darwinian theory
and he was often called 'Darwin's bulldog'. In his book Evidence as to Man's
Place in Nature (1863) offered proof for Darwin's thesis of natural
selection. He was Professor of the Royal College of Surgeons and President
of the Royal Society.
D. I. Loizos, 1996-1998
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CHARLES DARWIN
Charles Darwin (1809-1882) was an an English naturalist whose theory of
evolution is one of the greatest contributions ever made to science. Darwin
stated this theory in his book The Origin of Species (1859). In another book
called The Descent of Man (1871 ) he applied his theory to the evolution of
man from a primitive monkey-like animal. Both books aroused world-wide
controversy. Many considered them to be offensive, atheistic, blasphemous
and Darwin's caricatures were published in magazines. Although later
research has modified or disproved some of Darwin's findings, scientists
still accept his basic ideas.
Darwin was born in Shrewsbury and his father was a physician. As a youth
Darwin was interested in all living things. He read all the books on geology
and biology he could find and collected plant and animal specimens,
including fossils. In 1825 he began medical studies at the University of
Edinburgh but gave them up after two years. In 1828 he entered Cambridge
University to study theology getting a degree in 1831. He eventually
obtained a post as unpaid naturalist aboard the surveying ship H.M.S.
Beagle.
In 1831 the Beagle left on a five-year voyage to South American and
Australian waters. During this time Darwin observed and studied in many
remote regions of the world. He collected great numbers of plant and animal
specimens. From detailed notes of his observations he began to develop the
theory that was to make him famous. When he returned to England Darwin began
studying and investigating nature. In 1844 Darwin began to compile his
greatest contribution, Origin of Species, in which he proposed his theory of
natural selection. All life, he said, is a continuous struggle in which only
the fittest can survive. In this period Darwin discovered that the idea of
natural selection was not exclusively his. Alfred Russel Wallace ( 1823-1913
), a young naturalist, had developed similar ideas in an essay called "On
the Tendency of Varieties to Depart Independently from the Original Type."
Wallace sent this paper to Darwin for an opinion. Darwin took Wallace's
manuscript to a friend, Sir Charles Lyell, who decided that both Wallace's
and Darwin's ideas should be presented at the same time. On July 1,1858,
both papers were read at a meeting of the Linnaean Society of London.
After publication of Origin of Species in 1859, Darwin continued to
write on botany, geology, and zoology until his death in 1882. He is buried
in Westminster Abbey.
D. I. Loizos, 1996-1998
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THE FIRST HUMANS
Africa is the cradle of human race. Anthropologists have unearthed the
oldest human skeletons in East Africa in places such as Hadar, Olduvai,
Laetoli. One of the best preserved human remnants is a female skeleton found
at Hadar in Ethiopia. Anthropologists assembled about 40% of the young girl
that was given the nick name "Lucy". Lucy was dated between 3.6 and 3
million years ago and belongs to the Australopethicus category.
HADAR
Hadar's paleontological and anthropological significance was
discovered in 1968 by M. Taieb, a French geologist. Taieb organized a
geological and paleontological survey of the area in 1971, in which he was
joined by D.C. Johanson, Y. Coppens, and J. Kalb. These workers formed the
International Afar Research Expedition (INRE). They chose Hadar from the
many other available sites to begin intensive investigation mainly because
of its excellent preservation of faunal remains.
During the initial field season in 1973 the first early hominid fossils
were recovered from Hadar, a knee joint and a partial temporal. Nearly 6,000
fossils of mammals, a total of 87 species, were recovered in 1973 and in
subsequent seasons. In the fall of 1974 a larger team returned to continue
the search and soon made a discovery of hominid teeth.
At the end of November D.C. Johanson discovered at locality 288 the
partial skeleton of a tiny female hominid, which was nicknamed "Lucy." The
1975 field season brought even more hominid remains, this time at Locality
333. This locality has been interpreted as evidence for the catastrophic
death of a group of hominids. The 333 site yielded, by the close of
excavations during the 1976-1977 field season, hundreds of hominid fossil
fragments derived from at least 13 individuals representing all ages. All of
the Hadar fossils were returned after study to the National Museum of
Ethiopia in Addis Ababa, where they are permanently housed.
The Hadar Formation consists of at least 280 m. of sediment. Over 100
stratigraphic sections have been studied thus far, and it has been possible
to subdivide the sedimentary sequence into four stratigraphic members.
Radiometric dating has dated the top of the Hadar units at ca. 2.9 million
years (m.y.) ago. Dating for the lower units has been more controversial,
with estimates 3.6 and 3.3 m.y. ago. Thus it can be stated confidently that
the "Lucy" specimen is ca. 3 m.y. old, while some of the other,
stratigraphically lower Hadar hominids are at least 3.3 and possibly as much
as 3.6 m.y. old. [Source: Ian Tattersall, et al. eds, Encyclopedia of Human
Evolution and Prehistory (Chicago: St James Press, 1988), pp. 239-241]
STONE-TOOL MAKING
The first humans used sharp stones as tools. "The emergence of a
flaked-stone technology during the course of hominid evolution marks a
radical behavioral departure from the rest of the animal world and
constitutes the first definitive evidence in the prehistoric record of a
simple cultural tradition, or one based upon learning. Although other
animals Archaeological evidence shows a geometric increase in the
sophistication and complexity of hominid stone technology over time since
its earliest beginnings 3-2 m.y. ago. Stone is the principal material found
in nature that is both very hard and able to produce superb working edges
when fractured A wide range of tasks can be performed such as meat cutting
and bone breaking". [quoted from Tattersall et al.eds, op.cit., p. 542].
D. I. Loizos, 1996-1998
