Download
1 / 24
280 likes | 494 Views
Archaic Homo sapiens. Homo antecessor Homo heidelbergensis Homo neandertalensis. Archaic Homo.
E N D
Archaic Homo sapiens Homo antecessor Homo heidelbergensis Homo neandertalensis
Archaic Homo • For many years, scientists placed any problematic specimens displaying mixtures of "erectus-like" and "modern" traits into a confusing category: "Archaic" Homo sapiens (basically meaning any Homo sapiens that didn't look quite modern). • Recently, it has been proposed to separate these individuals into a distinct species. For this purpose, the names Homo antecessor &Homo heidelbergensis have been assigned.
Homo antecessor • The species Homo antecessor is another very controversial species designation. The species was designated by J.L. Arsuaga et al. to the remains of several individuals found at the Gran Dolina site, Spain. • The discovery was significant because the remains have been securely dated at over 780 kyr. This makes the material the earliest known European specimens. • The find breathed new life into the argument for the validity of H. heidelbergensis, as well as creating a whole new species: H. antecessor.
Homo antecessor traits • Has a marked double-arched browridge (like later Neanderthals and Chinese erectus). • An approximate brain size of 1000 cc. • Reduced mandibular thickness when compared to ergaster or early erectus. • Has small postcanines that resemble those of the habilines (habilis and rudolfensis), but they are still within the ergaster/erectus range. • Shovel-shaped maxillary incisors (ancestral condition).
Gran Dolina Site, Spain • The most complete specimen is Hominid 3, which is also the type specimen for antecessor. • This is unusual because Hominid 3 is a 10-year old, and therefore has not fully developed its skeletal characteristics. • The specimen was chosen because it highlighted all the features that the researchers were attempting to describe as typic of the species. • However, these features are all variable (even within the small sample from Gran Dolina itself. • Few researchers accept the antecessor taxon, instead considering the material heidelbergensis.
Homo heidelbergensis • Homo heidelbergensis is the species name now given to a range of specimens from about 800,000 years ago to the appearance of anatomically modern Homo sapiens (the species to which we belong). • The species name was originally proposed for the fossil mandible discovered at Mauer, a town near Heidelberg, Germany. It is a nearly complete early human mandible that is very robustly built, but lacks a chin. • Additional finds of early humans with morphological attributes of both modern humans and Homo erectus have shown that the transition from early and middle Pleistocene forms and the morphology of modern humankind was not a neat transition that could be easily explained.
This mandible was found by a workman in the Rösch sandpit just north of the village of Mauer near Heidelberg, Germany, in 1907. The workman showed the find to the anatomist O. Schoentensack, who provided the initial description of the specimen. The mandible is complete with only the premolars and first two molars on the left side missing. The molars were recovered separately, although the premolars were lost.
Homo heidelbergensis • The mandible itself is large, and robustly built like that seen in Homo erectus, with broad ascending rami. The corpus of the mandible is deep and thicker than a modern human's. The lack of a projecting chin is another morphological difference from modern humans. Schoentensack proposed the species name Homo heidelbergensis for the Mauer specimen. This assignment has been problematic over the years. The robust morphology of the jaw shows affinities to Homo erectus populations from the same time period, yet the tooth morphology is decidedly more "modern" in appearance. Most researchers agree that the Mauer mandible is not Homo erectus. For a long time many scientists placed the mandible a rather confusing taxon: "Archaic" Homo sapiens. Recently, members of this taxon have been separated at the species level and given a separate species name: Homo heidelbergensis. • Unfortunately, there is no way to absolutely date the Mauer specimen; that is, determine exactly how old the specimen is. However, faunal correlation (comparing the animal fossils found at this site with other sites for which dates have been determined) has placed the find within the Middle Pleistocene, perhaps 500,000 years old.
Kabwe Skull • Once thought to be less than 40,000 years old, the Kabwe skull (also known as the Broken Hill skull) was used at one time to validate the supposed "primitiveness" of African peoples, demonstrating that while Europeans had evolved to the "level" of Cro-Magnon, African populations still looked essentially like Homo erectus. • This assumption was shown to be flawed on many accounts, most crucially in that the date for this site based on the associated animal fossils found is at least 125,000 years old, and is probably significantly older. • Some researchers have proposed that Kabwe may be a member of the African population from which all modern humans descended, although this cannot be definitively proven.
The braincase profile is low and slopes back from a large supraorbital torus reminiscent of earlier H. erectus specimens. There is also the remnant of a sagittal keel and an occipital torus at the back of the skull, also recalling H. erectus. However, the face is more modern in appearance (less prognathic, flatter) and the brain size of about 1300 cc. is larger than seen in H. erectus. Thus, this cranium preserves many traits that are reminiscent of earlier H. erectus and hints of more modern traits known later in H. sapiens.
The cranium shows evidence of disease and wounds that occurred in the lifetime of this individual. • Ten of the upper teeth have cavities, and dental abscesses of the upper jaw are clearly visible in the upper photograph (above the right incisor/canine) and the middle photograph (above the first molar). • Additionally, a partially healed wound is visible in the bottom two photographs, above and anterior of the hole for the ear. • This wound measured roughly a quarter-inch across, and was made by either a piercing instrument or the tooth of a carnivore. Exactly which is unclear
Homo sapiens neanderthalensisNeandertals (ca. 200-32 kya) • Species restricted to Europe, eastern Middle East during height of Ice Age • Evolved to be specifically cold-adapted: • Short and stocky body type • Large nose (nasal passages for warming air) • Barrel chest (also for warming air) • Long, low, thick skull but with large cranial capacity (1250-1750 cc) • Heavy brow ridge
Not the “Cave Men” they were made out to be! • First to bury dead • First to create art on rocks and bone • Elaborate Stone and Bone Tool technology • Mousterian tools • Some degree of altruism • Old Man of La Chapelle • Individual from Shanidar
Mousterian Tools: Period of stone tools associated with Neandertals
