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Dryopithecus
Dryopithecus is a genus of extinct great apes from the middle–late Miocene boundary of Europe 12.5 to 11.1 million years ago (mya). Since its discovery in 1856 there is currently only one uncontested species, the type species D. fontani, though there may be more. The genus is placed into the tribe Dryopithecini, which is either an offshoot of orangutans, African apes, or is its own separate branch. For the background to human evolution, the most important European fossil ape is Dryopithecus. The discoveries from France, Spain, Hungery and other sites have extended the sample of Dryopithecus to include relatively complete crania and a diversity of postcranial elements. All remains date to between 13 million and 10 million years ago, likely after the common ancestor of the Asian and African ape clades. The features of the cranial material of Dryopithecus are generally more similar to living African apes than to orangutans, although fossil Sivapithecus and Dryopithecus are very similar to each other Chronology: Middle Miocene (15-10 million years ago) Environmental Background: The late Miocene was the beginning of a drying trend in Europe. Increasing seasonality and dry spells in the Mediterranean region and the emergence of a Mediterranean climate likely caused the replacement of forestland and woodland by open shrubland; and the uplift of the Alps caused tropical and warm-climate vegetation in Central Europe to retreat in favour of mid-latitude and alpine flora. This likely led to the extinction of great apes in Europe. European great apes likely went extinct during a drying and cooling trend in the Late Miocene which caused the retreat of warm-climate forests. Distribution: The original European ape, Dryopithecus fontani was discovered in France. Among the first evidence for ancient primate evolution, these fossil remains have been joined in recent years by newer fossils excavated from Spain, Hungary, and as far east as the Caucasus. Salient Anatomical Features: Based on measurements of the femoral head of the Spanish IPS41724, the living weight for a male Dryopithecus was estimated to be 44 kg (97 lb).[11]. They lived in a seasonal, paratropical climate, and may have built up fat reserves for winter. Dryopithecus teeth are most similar to those of modern chimps. The teeth are small and have a thin enamel layer. Dryopithecus has a slender jaw, indicating it was not well-suited for eating abrasive or hard food. Like modern apes, the males had longer canines than females, which is typically correlated with high levels of aggression. The molars are wide, and the premolars wider. It has a wide roof of the
Sk. Hedayet Hossain, Assistant Professor, Department of Anthropology
Ramsaday college mouth, a long muzzle (prognathism), and a large nose which is oriented nearly vertically to the face. In total, the face shows many similarities to the gorilla; since early to middle Miocene African apes do not share such similarities, gorilla-like features likely evolved independently in Dryopithecus rather than as a result of close affinities. The pattern of cusps and grooves on its molar teeth is similar to the great apes and humans with grooves between the cusps arranged in the form of a Y. This pattern is often called the Y-5 dental pattern. The humerus, measuring an approximate 265 mm (10.4 in), is similar in size and form to the bonobo. Like in bonobos, the shaft bows outward, and the insertion for the triceps and deltoids was poorly developed, suggesting Dryopithecus was not as adept to suspensory behaviour as orangutans. The femoral neck, which connects the femoral head to the femoral shaft, is not very long nor steep; the femoral head is positioned low to the greater trochanter; and the lesser trochanter is positioned more towards the backside. All these characteristics are important in the mobility of the hip joint, and indicate a quadrupedal mode of locomotion rather than suspensory. Other features link Dryopithecus to the living apes. The elbow joint was capable of a full range of extension, which is not possible in quadrupeds like monkeys. The face was downward-directed like living chimpanzees and gorillas, called klinorhynch, unlike orangutans and Sivapithecus (Begun, 2003). Dryopithecus likely predominantly ate ripe fruit from trees, suggesting a degree of suspensory behaviour to reach them, though the anatomy of a humerus and femur suggest a greater reliance on walking on all fours (quadrupedalism). Phylogeny: Dryopithecus was of the many prehistoric primates of the Miocene epoch and was a close contemporary of Pliopithecus. These tree-dwelling apes originated in eastern Africa about 15 million years ago, and then, much like its hominid descendants millions of years later (although Dryopithecus was only remotely related to modern humans), the species radiated out into Europe and Asia. The initial dental discoveries of Dryopithecus identified it as a fossil ape on the basis of the pattern of cusps and grooves on its molar teeth - the Y-5 dental pattern. In addition to the phylogenetic significance of the molars, their form probably indicates that the basic dietary niche of more recent apes arose at their origin and initial radiation.
Sk. Hedayet Hossain, Assistant Professor, Department of Anthropology