gamma-ray background
gamma-ray background Diffuse celestial radiation extending up to energies of at least 200 MeV. On a coarse scale, the gamma-ray background appears to be uniformly distributed (isotropic), indicating that it originates outside our Galaxy. Its low intensity rules out the steady-state theory of the Universe. Three possible sources of at least part of the radiation are the annihilation of matter and antimatter, active galaxies, and the explosion of primordial black holes.
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Ancestors go South.(Australopithecus fossils found in South Africa date to 4 milion years ago)(Brief Article)
Magazine article from: Science News; 4/26/2003; ; 541 words
; ...Science. A mix of new and already excavated Australopithecus fossils, found in two caves, date to 4...suspect that the bones represent two forms of Australopithecus. An Australopithecus species of comparable age lived in eastern...
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Age of pre-human skeleton revised Australopithecus now believed buried about
Newspaper article from: Oakland Tribune; 4/25/2003; ; 700+ words
; ...studies on the Sterkfontein fossils. Australopithecus is an extinct hominid species that...Ethiopia, was identified as a type of Australopithecus. The new age dating technique suggests...than Lucy. Granger said only an Australopithecus fossil found in Kenya is older than...
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The hominid who ate antelope for dinner.(Australopithecus garhi discovered in Ethiopia)(Brief Article)
Magazine article from: U.S. News & World Report; 5/3/1999; ; 700+ words
; ...call the new creature Australopithecus garhi. The first word...the even more primitive Australopithecus afarensis, better known...between Lucy and Homo--Australopithecus africanus, a species...
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Revising human origins: a new fossil find adds one more member to the family tree. (Australopithecus ramidus)
Magazine article from: U.S. News & World Report; 10/3/1994; ; 700+ words
; ...the oldest known human ancestor was Australopithecus afarensis, which first appeared...kin. The scientists dubbed them Australopithecus ramidus, from the word ramid, which...Homo habilis 2 million years ago Australopithecus africanus 3 million years ago Australopithecus...
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These spines were made for walking.(australopithecus afarensis)(research)(Brief Article)
Magazine article from: Science News; 4/23/2005; 700+ words
; ...anatomy of spinal columns from the 3.2-million-year-old Australopithecus afarensis skeleton known as Lucy and a pair of roughly 2.5-million-year-old Australopithecus africanus specimens. As in modern people, the spines of the...
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Team unearths oldest known human ancestor. (Australopithecus ramidus)
Magazine article from: Science News; 10/1/1994; ; 700+ words
; ...California, Berkeley, assigns them to a new species, Australopithecus ramidus. For nearly 20 years, the earliest hominid remains...anatomical differences to qualify as a new genus distinct from Australopithecus, argues Bernard Wood, an anthropologist at the University...
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Humankind's first steps.(4.2-million-year-old Australopithecus anamensis is earliest known bipedal primate)(Brief Article)
Magazine article from: Newsweek; 8/28/1995; ; 700+ words
; ...probably the oldest direct human ancestor ever identified. Australopithecus anamensis lived some 4.2 million year ago, and it takes...only 3.6 million years. Our oldest known ancestor was Australopithecus afarensis, a small creature that came to light in 1974...
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Boisei's adaptable ways. (Australopithecus boisei more adaptable than australopithecines, which are more closely related to humans)(Anthropology)(Brief Article)
Magazine article from: Science News; 4/19/1997; ; 576 words
; Australopithecus boisei, a member of a lineage in the human evolutionary family that died out around 1 million years ago, combined huge jaws designed...
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Early hominid rises again.(Australopithecus anamensis identified from fossils found in Kenya)(Brief Article)
Magazine article from: Science News; 5/16/1998; ; 700+ words
; ...human evolutionary family that lived about 4.1 million years ago, a research team reports. The creature, dubbed Australopithecus anamensis, was the earliest known human ancestor capable of walking upright. A. anamensis was first identified...
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Hominids: down-to-earth or up tree? (Australopithecus afarensis)
Magazine article from: Science News; 4/9/1994; ; 700+ words
; For more than 15 years, the way in which Lucy and other members of Australopithecus afarensis, the earliest known species in the human evolutionary family, moved about has sparked considerable debate. One side...
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Australopithecus
Book article from: The Columbia Encyclopedia, Sixth Edition
Australopithecus , an extinct genus of the hominid...generally recognized, including Australopithecus afarensis, A. africanus, A...1995. The first remains of an Australopithecus recovered outside of E or S Africa...
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Man
Book article from: The Oxford Companion to the Earth
...contains four genera: Ardipithecus, Australopithecus, Paranthropus, and Homo. The family...both relationships of this form with Australopithecus species and its mode of locomotion...experienced in open country. The genus Australopithecus contains three species, all from...
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Quaternary Period
Book article from: World of Earth Science
...before modern humankind ( Homo sapiens ) appeared. Many of these species, including Australopithecus anamensis, Australopithecus afarensis, Australopithecus garhi , and Australopithecus africanus were only collateral rungs on the ladder of...
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Pliocene Epoch
Book article from: World of Earth Science
...of primates and human evolution, are fossilized remains of Ardipithecus ramidus, Australopithecus anamensis, Australopithecus afarensis, Australopithecus garhi , and Australopithecus africanus that date to the Pliocene Epoch. Although...
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early humans
Book article from: A Dictionary of World History
...southern Africa in 1924 and named Australopithecus africanus (southern ape of Africa...years ago) and most ape-like is Australopithecus afarensis , now known from eastern...species is often linked closely to Australopithecus africanus (3–2 million...
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