S. tchadensis is very primitive but also exhibits advanced canine reduction, significantly reduced prognathism, and lacks a honing complex. Position of the foramen magnum suggests S. tchadensis was bipedal, which, if true, makes this specimen the oldest evidence of hominin bipedalism.
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Sahelanthropus tchadensis. Where Lived: West-Central Africa (Chad) When Lived: Sometime between 7 and 6 million years ago. Sahelanthropus tchadensis is one of the oldest known species in the human family tree. This species lived sometime between 7 and 6 million years ago in West-Central Africa (Chad).
Although we have only cranial material from Sahelanthropus, studies so far show this species had a combination of ape-like and human-like features. Ape-like features included a small brain (even slightly smaller than a chimpanzee’s), sloping face, very prominent browridges, and elongated skull.
The discoverers claim that S. tchadensis has numerous derived hominin features and is therefore the oldest known human ancestor after the split of the human line from that of the chimpanzees. If the remains are from a direct human ancestor, then the status of the australopithecine group as human ancestors is questioned.
The skull of S. tchadensis is very robust, with a chimp-sized brain and pronounced ape-like muscle attachments. While only fragmentary postcranial material has been discovered, some researchers claim that the foramen magnum is anteriorly oriented, suggesting an upright and bipedal hominin.
Before 2001, early humans in Africa had only been found in the Great Rift Valley in East Africa and sites in South Africa, so the discovery of Sahelanthropus fossils in West-Central Africa shows that the earliest humans were more widely distributed than previously thought.
Although the placement of the foramen magnum appeared similar to humans', other aspects of the skull would have prevented the species from keeping its head upright—and therefore it couldn't have been a bipedal walker, the team concluded. Thus, they suggested, Sahelanthropus was not a hominid, just some kind of ape.
“Is Sahelanthropus our ancestor? We will never know! He might have been part of a population of 'bipedal apes' that was an evolutionary dead end.” Spoor sees Toumaï as a key specimen regardless of whether it belongs in our family tree.
The foramen magnum of Sahelanthropus is positioned more anteriorly than that of the chimpanzee and is closer to the human condition, suggesting to Brunet et al. (2002, 2005) that it held its head in a similar fashion to humans and was thus bipedal.
tchadensis has advanced features, such as a thickened brow ridge, that are more similar to those of later fossil Homo and different from all australopithecines. Others interpret the remains as being: a common ancestor of humans and chimpanzees. related to both humans and chimpanzees, but not an ancestor of either.
PHYSICAL CHARACTERISTICS The skull of S. tchadensis is very robust, with a chimp-sized brain and pronounced ape-like muscle attachments. While only fragmentary postcranial material has been discovered, some researchers claim that the foramen magnum is anteriorly oriented, suggesting an upright and bipedal hominin.
Which of the following is a derived trait of Sahelanthropus tchadensis? choppers, cobbles, flakes, and bone tools. What is the earliest date associated with Homo erectus fossils in Asia?
They are from different fossil localities, though may have overlapped in time. S. tchadensis is known from teeth, several mandibles, and a cranium, while O. tugenensis is known from teeth, three partial femora, a distal humerus, and a proximal manual phalanx.
Sahelanthropus tchadensis is an extinct species of the Homininae (African apes) dated to about 7 million years ago, during the Miocene epoch. The species, and its genus Sahelanthropus, was announced in 2002, based mainly on a partial cranium, nicknamed Toumaï, discovered in northern Chad.
ChadIn more recent decades, anthropologists have determined that bipedalism has very ancient roots. In 2001, a group of French paleoanthropologists unearthed the seven-million-year-old Sahelanthropus tchadensis in Chad.
The advantages The host of advantages bipedalism brought meant that all future hominid species would carry this trait. Bipedalism allowed hominids to free their arms completely, enabling them to make and use tools efficiently, stretch for fruit in trees and use their hands for social display and communication.
What the name means. The genus name is made of two words. ‘Sahel’ is the area of Africa near the southern Sahara where the fossils were found and ‘anthropus’ is based on the Greek word meaning ‘man’. The species name is based on Chad, in recognition that all specimens were recovered from that country.
the lack of cranial remains makes estimates difficult, but brain size is estimated at about 320-380cc (similar to that of a chimpanzee) Body size and shape. the lack of skeletal remains makes estimates difficult. This species was probably similar in size to modern chimpanzees. Jaws and teeth.
Environment and diet. The ancient environment where the fossils were found consisted of lake, forest, river, and wooded savanna. Thousands of vertebrate fossils have also been found at the site including elephants, giraffes, antelopes, hippopotamus, crocodiles, lizards, monkeys, fish and wild boar.
position of the foramen magnum suggest that it may have been bipedal, although some experts dispute this interpretation. scars left on the fossil ised bones from its neck muscles suggest the species was a quadruped but others claim that the neck muscles attached at the back of the neck in the same way as bipeds.
The femur was not recognised as possibly belonging to a hominid until 2004. As most of the diagnostic features are missing, the question of whether the femur represents a biped (or hominin) is extremely difficult. What the name means. The genus name is made of two words.
The discoverers claim that S. tchadensis has numerous derived hominin features and is therefore the oldest known human ancestor after the split of the human line from that of the chimpanzees. If the remains are from a direct human ancestor, then the status of the australopithecine group as human ancestors is questioned.
The Sahelanthropus tchadensis specimen (see Figure 6.2) was discovered in 2001 at the site of Toros-Menalla, in the Djurab Desert of northern Chad, by Michel Brunet and associates. Brunet’s incredible years-long quest for hominins in that area is documented in the NOVA series, Becoming Human ( www.pbs.org/wgbh/nova/evolution/becoming-human.html). The species name translates to “human from the sahel of Chad.” The sahel is the region of dry grasslands south of the Sahara desert. The skull has been nicknamed “ Toumai ” in the Dazaga language, meaning “hope of life.”
As mentioned, the holotype (the fossil (s) from a particular individual that are assigned to and used to define the characteristics of a species) was discovered at the desert site of Toros Menalla (see Figure 6.3). Unless fossils are discovered elsewhere, it is impossible to speculate about the extent ...
The species name translates to “human from the sahel of Chad.”. The sahel is the region of dry grasslands south of the Sahara desert. The skull has been nicknamed “ Toumai ” in the Dazaga language, meaning “hope of life.”. Cast of the Sahelanthropus tchadensis holotype cranium.
PHYSICAL CHARACTERISTICS. The skull of S. tchadensis is very robust, with a chimp-sized brain and pronounced ape-like muscle attachments. While only fragmentary postcranial material has been discovered, some researchers claim that the foramen magnum is anteriorly oriented, suggesting an upright and bipedal hominin.
Sahelanthropus means “Hope of life” in the local Ghouren language of Chad. Tchadensis simply means “From Chad.” Chad is a relatively large country in north Africa, west of the Sudan, Ethiopia and Somalia.
Sahelanthropus tchadensis is not without controversy. And said controversy has only grown with time…
A partial left femur (TM 266-01-063) was recovered in July 2001 at Toros-Menalla, Chad, at the same fossiliferous location as the late Miocene holotype of Sahelanthropus tchadensis (the cranium TM 266-01-060-1). It was recognized as a probable primate femur in 2004…
AFTER more than a decade in limbo, a crucial fossil of an early human relative has finally been scientifically described.
The oldest known footprints of pre-humans were found on the Mediterranean island of Crete and are at least six million years old, says an international team of researchers from Germany, Sweden, Greece, Egypt and England, led by Tübingen scientists Uwe Kirscher and Madelaine Böhme of the Senckenberg Center for Human Evolution and Palaeoenvironment at the University of Tübingen….
This places the Trachilos footprints in Crete at around the same age as the fossils of the upright-walking Orrorin tugenensis from Kenya… Six million years ago, Crete was connected to the Greek mainland via the Peloponnese.