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| Reconstruction and animation of Australopithecus afarensis on Laetoli which causes footprints one of the best known of the early hominins |
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| 3D Reconstruction of Australopithecus afarensis in 3ds Max |
Australopithecus
afarensis:
It is thought that
Australopithecus afarensis could be the ancester of the genus Homo, to which
modern humans- Homo sapiens - belong.
Australopithecus afarensis is one of the best known of the early hominins. The
fragmented remain of several hundred individuals have been found in East Africa
, including males females and juveniles.Research on the material has revealed
evidence for both terrestrial and arboreal lifestyles, and extreme sexual
dimorfphisam. Discovery:  On November 24, 1974,
fossils of one of the oldest known human ancestors, an Australopithecus
afarensis specimen nicknamed “Lucy,” were discovered in Hadar, Ethiopia. On
November 24, 1974, fossils of one of the oldest known human ancestors, an
Australopithecus afarensis specimen nicknamed “Lucy,” were discovered in Hadar,
Ethiopia. The team that excavated her remains, led by American
paleoanthropologist Donald Johanson and French geologist Maurice Taieb, nicknamed
the skeleton “Lucy” after the Beatles song “Lucy in the Sky with Diamonds,”
which was played at the celebration the day she was found. Lucy, about 3.2
million years old, stood only a meter (3.5 feet) tall. She had powerful arms
and long, curved toes that paleontologists think allowed her to climb trees as
well as walk upright. %20and%20Maurice%20Taieb%20(right)%20in%201974,%20studying%20the%20bones%20of%20an%20Australopithecus%20afarensis%20specimen%20later%20named%20Lucy.jpg) Donald Johanson (left) and Maurice Taieb (right) in 1974, studying the bones of an Australopithecus afarensis specimen later named Lucy Famed geologist Maurice
Taieb, whose discovery of the Hadar formation in the Afar region of Ethiopia
became key to studying human evolution, has died at the age of 86, the French
National Centre for Scientific Research reports. In 1974, the
3.2-million-year-old bones of Australopithecus afarensis, better known as Lucy,
were found in the formation. Taieb was born in
Tunisia on July 22, 1935. According to a 2006 profile in Nature, he spent his
youth accompanying his uncle, a merchant, around Africa. Eventually, he moved
to his mother’s native land of France, and earned his geology PhD from the
University of Paris VI in 1974. While exploring in 1968,
Taieb had discovered a cache of snail fossils in what would be known as the
Hadar Formation. He suspected that, due to the site’s proximity to where
tectonic plates meet and push ancient rocks to the surface, the area could
yield many other fossils, perhaps even those of early humans, and encouraged
paleoanthropologists to investigate the site. In 1972, as a graduate student,
he founded the International Afar Research Expedition (IARE) to thoroughly
investigate the area. Two years later, Taieb, along with his IARE codirectors,
paleoanthropologists Donald Johanson and Yves Coppens, made one of the most
important discoveries in the field of human evolution. Taieb and Coppens were
on Johanson’s field team in 1974 when they found 52 bones and fragments of a
member of the species Australopithecus afarensis, a hominid that lived from
2.9-3.9 million years ago. While her upper half indicated a small brain size
and features of early apes, her lower body had features indicative that she was
bipedal. This particular specimen dated back 3.2 million years and yielded
enough information to name the species, and to contextual previously-discovered
A. afarensis bone fragments from discoveries made during preceding decades. At
the time, a particular Beatles song was popular in camp, leading the specimen to
be nicknamed “Lucy.”  Johanson, who is the
founder of the Institute of Human Origins at Arizona State University, tells
The Scientist by email that Taieb was “an intrepid explorer and one of the most
generous human beings I have ever known. His early geological field work in the
Afar Region of Ethiopia prompted paleoanthropologists, biologists,
archaeologists and geologists to follow in his footsteps.” “Maurice Taieb’s
inspiration led to an unparalleled record for human origins in Ethiopia that
stretches back to 6 million years ago,” Johanson continues, referring to the
wealth of fossils found over the years at the site. “I shall miss him as a
close friend and valuable colleague.” Politics and conflicts
in the region brought myriad complications to Taieb’s expeditions over the
decades following Lucy’s discovery, prompting him to explore other sites across
other eastern Africa and other opportunities. In 1996, he joined the faculty of
Aix-Marseille University, part of the French National Centre for Scientific
Research, to study geology, paleoclimatology, and climatology, eventually
becoming the Director of Research for the center.  The morphology of Au. afarensis is a mosaic of apelike features and
humanlike traits shared by later hominins. The face is strongly prognathic, and
the anatomy of the snout is quite apelike. Certain details of the dentition
(the arrangement of the teeth) are reminiscent of apes, and the dental
arch—that is, the curve of the row of teeth in each jaw—is apelike. (The dental
arch of Au. afarensis is rectangular in outline, and thus it is distinct from
the parabolic dental arch found in modern humans.) The cranial capacity of Au.
afarensis ranges from 380–530 cc (23.2–32.3 cubic inches), about one-third the
size of that of a modern human. In addition, numerous anatomical details in the
mandible and skull are indicative of an apelike ancestry and suppport the
distinction of Au. afarensis from other species of Australopithecus.  Other morphological characteristics in Au. afarensis are commensurate with a terrestrial,
striding, bipedal gait. The pelvis, hip, knee, and ankle exhibit, in many
details, an anatomy and function very similar to that observed in modern
humans. The curved finger and toe bones are likely evolutionary remnants left
over from an apelike ancestor. While the upper limb is relatively long compared
with the length of the lower limb, the spine exhibits humanlike curvatures, and
the foot has a convergent great toe and strong arches as shown in modern
humans.  Sexual dimorphism—that is, the differences in appearance between males and
females—was marked in Au. afarensis. Males weighed 45–68 kg (99–150 pounds)
compared with 30 kg (66 pounds) for females. Males stood about 151 cm (roughly
5 feet) tall, whereas females were about 105 cm (about 3 feet 5 inches) tall.
Significant sexual dimorphism is typical of early hominin species. Another
example is “Ardi,” a skeleton of Ar. ramidus assigned to a female that weighed
110 pounds (50 kg), standing 122 cm (roughly 4 feet) tall; males must have been
taller and relatively very large.  Hominin fossils (which
included an immature partial skeleton, jaws, and teeth) discovered at the
northern Tanzanian site of Laetoli, dating to approximately 3.6 mya, are among
the most ancient examples of Au. afarensis. Investigation at Laetoli unveiled a
layer of volcanic ash that preserved thousands of animal footprints. Amazingly,
two Au. afarensis individuals left a 24.4-metre- (80-foot-) long trail of their
own footprints frozen in time. These footprints were made by an arched foot
that possessed a forward-pointing great toe, a strong heel strike, and powerful
toe-off (that is, where the toes leave the ground during a step)—all of which
are hallmarks of human bipedalism. In 1995 a mandible
resembling that of Au. afarensis came to light from a site near Koro Toro in
northern Chad. It is 3.5 million years old and was assigned to a new species,
Au. bahrelghazali. Most of its anatomical features are identical to those of
Au. afarensis, however. The discovery of Au. bahrelghazali extends the
geographic range of Australopithecus some 2,500 km (1,500 miles) west of
Africa’s Great Rift Valley (see East African Rift System). A curious cranium
discovered in 1997 at Bouri in the Afar region of Ethiopia was placed in the
species Au. garhi (2.5 mya). The species takes its name, garhi, from the Afar
word for surprise. The specimen possessed a number of traits in common with Au.
afarensis, most notably the prognathic face, but the cheek teeth were
significantly larger than any assigned to Au. afarensis. Another feature of the
Bouri specimen was a crest running along the midline of the braincase, the
sagittal crest. The combination of the large teeth, large jaw, and sagittal
crest—which are all features of the robusts—and the ancestral anatomy of Au.
afarensis suggest that Au. garhi descended from Au. afarensis and that it
evolved in the direction of the robust Australopiths.
Maurice Taieb in 2020 A partial skeleton was
found some 300 meters (984 feet) away, but it could not be associated with the
cranium. Stone tools and cut-marked animal bones lay nearby also, however,
their association with the cranium could not be confirmed. Australopithecus
afarensis The Laetoli footprints:The small group walk through a desolate landscape leaving
track of footprints in recently fallen volcanic ash.  Size difference ;he Laetoli are those of different sizes individual
walking together . One individual was upto 165 cm (5 ft 5 inch) ,while the
other one less than 145cm (4 ft 9 inch) .This striking size difference may mean
there was significant sexual dimorphism- size betweens the sexes - among
Australopithecus afarensis However others believe that the footprints were made
by one species.  Volcanic Eruption: The sadiman Volcano
located some 20 km east of the site where the Laetoli footprints tracks were
laid down . It was very active 3.6 million years ago, and frequent eruptions
had formed a conocal shape profile,Today the volcano is long extinct and its
slopes are greatly eroded. Associated Animals: As the habitat of this
part of the East Africa was similar to that exsisting today,it is not
surprising that the animal life was also similar .More than 20 species of
savanna-based animals left their tracks alongside Australopithecus afarensis
including Elephants,Giraffes,Antelope,Rhinoceroses, Buffelo.The gigantic
Deinotherium(ancient elephant) is shown
here. Footprints formation: The Laetoli footprints
tracks were formed by a specific sequence of events.Aninitial eruption left a
fine layers of powdery ash through which the Hominins left their mark. A soft
rain shower ,followed by sunshine,had the effect of solidifying this layer,
before subsequent eruptions covered the tracks until they were eventually
unearthed Australopithecus afarensis The Laetoli footprints withThe gigantic Deinotherium pics:        |
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