Hadar

"Lucy", a 3.2-million-year-old Australopithecus afarensis fossil discovered in Hadar, Ethiopia
Site location in Ethiopia
Location	Mille district, Afar Region,  Ethiopia
Region	Eastern Africa
Coordinates	11°10′01″N 40°37′59″E / 11.167°N 40.633°E / 11.167; 40.633
Type	Archaeological Paleontology
History
Periods	Middle - Late Pliocene
Site notes
Excavation dates	1970, 1972, 1973, 1974, 2000
Archaeologists	Donald Johanson Maurice Taieb Denis Geraads Zeresenay Alemseged
Condition	Excavated
Ownership	Ethiopian Government

Hadar or Hadar Formation (also spelled Qad daqar, Qadaqar; Afar "white stream ")^[1] is a paleontological fossil site located in Mille district, Administrative Zone 1 of the Afar Region, Ethiopia, 15 km upstream (west) of the A1 road's bridge across the Awash River (Adayitu kebele).^[2]

It is situated on the southern edge of the Afar Triangle (part of East Africa's Great Rift Valley), along the left banks of the Awash River, between two minor tributaries, the eponymous Kada Hadar and the Kada Gona.^[2] In 1972, Taieb organized a small exploratory reconnaissance of the Afar region to investigate more paleontological finds there. After six weeks of exploration, the party focused on the Hadar site.^[3]

The site has yielded some of the most well-known hominin fossils, including "Lucy". These hominin fossils range in age from approximately 3.42 to 2.90 million years ago. These finds give us a greater understanding of hominin evolution during this period.

It is postulated that the specimens in the region were deposited by way of a large river system with associated crevasse channels/splays, deltas, and distributary channels, as well as periodic transgressions of paleolake Hadar located east of the research area (Aronson and Taieb, 1981, Tiercelin, 1986, Campisano and Feibel, in press) possibly related to geological activity or climatic cycles in at least the Kada Hadar Member (Yemane et al., 1996, Yemane, 1997, Campisano and Feibel, in press)."

According to Jon Kalb, early maps show caravan routes passing within 10 to 15 km of Hadar but not through it. The British explorer L.M. Nesbitt passed 15 km west of Hadar in 1928.^[1]

Geology

The region's rocks consist mainly of mudstones, siltstones, fine-grained sandstones and volcanic tuffs. The region of Hadar has been divided into four geologic members — Basal (~3.8–3.42 Ma), Sidi Hakoma (~3.42–3.26 Ma), Denen Dora (~3.26–3.2 Ma), and Kada Hadar (<~3.2 Ma)—with three tuffs (Sidi Hakoma Tuff , Triple Tuff and Kada Hadar Tuff ) separating the four members.

The Sidi Hakoma member tends towards high rainfall and low seasonality. The overlying Denan Dora Member was a grassland habitat. Finally, the Kada Hadar Member was an even more open and arid habitat, as seen in the high abundance of antilopines, which frequent these types of terrains.^[3]

Paleontology

The first paleo-geological explorations of the Hadar area were conducted by Maurice Taieb. He found Hadar in December 1970 by following the Ledi River, which originates in the highlands north of Bati to empty into the Awash River. Taieb recovered several fossils in the area and led a party back to Hadar in May 1972. In October 1973, 16 individuals with the International Afar Research Expedition (IARE) arrived at Hadar and camped there for two months during which the first hominin fossil was found. (Taieb claims in his 1985 book Sur la Terre des premiers Hommes to have discovered the Hadar fields in 1968, but Kalb argues that claim to be incorrect.)^[4] The IARE party examined a series of sedimentary layers called the Hadar Formation, which was dated to the late Pliocene to early Pleistocene epochs (3.5 to 2.3 million years ago).^[5]

Discovery of Lucy

The anthropologist Donald Johanson, a member of the 1973 expedition to Hadar, returned the next year and discovered the fossil hominin "Lucy" in the late fall of 1974.^[6] He spotted a right proximal ulna in a gully, followed by an occipital bone, a femur, some ribs, a pelvis, and a lower jaw. Within two weeks, nearly 40% of the hominoid skeleton had been identified and cataloged.^[7] Lucy is the most famous fossil to have been found at Hadar. Lucy is among the oldest hominin fossils ever discovered^[6] and was later given the taxonomic classification Australopithecus afarensis. (The name 'Lucy' was inspired by the song "Lucy in the Sky with Diamonds" by The Beatles, which happened to be playing on the radio at base camp.)

Specimens and inferences

In 1975, Donald Johanson made another discovery at a nearby site in Hadar: 216 specimens from approximately 17 individuals, most likely related and varying in age, called AL 333 (colloquially referred to as the "First Family").

About thirty years later in nearby Dikika, another Australopithecus afarensis fossil skeleton was found in a separate outcrop of the Hadar Formation across the Awash River from Hadar. The skeleton is of a three-year-old girl later named "Selam," which means peace in Amharic Ethiopian languages.

In 1973 and 1974 when the first anatomical discoveries were made, their size and shape pointed towards a variety of taxa, but further research has confirmed that only one hominin taxon is present here. The first find there was a fossil knee joint estimated to date from 3.4 million years ago. Since then, the Hadar research area has yielded 370 specimens of A. afarensis, one specimen of Homo, and 7571 additional vertebrate specimens.

The specimens recovered display a variety of different primitive cranial post features, which indicate A. afarensis is distinct from other species of Australopithecus: small cranial capacity, palate similar to African apes (parallel tooth rows, shallow, long from front to back, narrow from side to side), primitive occipital, basal cranium anatomy, high frequency of unicuspid third premolars, prognathic face, and primitive mandibular anatomy. Postcranially, the pelvis, knee, ankle, and foot indicate habitual, terrestrial bipedalism, but ape-like curved finger and foot bones are retained ancestral ape-like features.^[3]

Paleofauna

Although Australopithecus is well-known for its discovery since the 1970s, other specimens from the Hadar Formation contain several fossil remains of artiodactyls, perissodactyls, carnivorans, proboscideans, and other African species that are well preserved. The bovids found in the formation included the Aepycerotini (Aepyceros), Alcelaphini (Damalborea and Parmularius), Antilopini (Gazella), Bovini (Ugandax and Pelorovis), Caprini (Budorcas), Cephalophini, Hippotragini (Oryx), Neotragini (Raphicerus and Madoqua), Reduncini (Kobus), and Tragelaphini (Tragelaphus).^[8][9][10] Artiodactyls outside the bovid family were present within the formation as well, namely the giraffids (Giraffa and Sivatherium), Hippopotamidae (Hippopotamus), and suids (Kolpochoerus, Notochoerus, and Nyanzachoerus).^[11] While a definitive list of carnivorans found within the Hadar Formation has yet to be compiled, confirmed genera that were found within the Hadar Formation include canids (Canis and Nyctereutes), felids (Dinofelis,^[12] Leptailurus, Felis, Homotherium, and Panthera), hyaenids (Chasmaporthetes, Ikelohyaena, Crocuta, Hyaena, and cf. Pliocrocuta),^[13] herpestids (Herpestes and cf. Helogale), mustelids (Mellivora, Enhydriodon,^[14] and cf. Poecilogale), and the viverrid (cf. Civettictis). Mammals within the formation outside the artiodactyl and carnivoran families include a bat (indeterminate), the leporid (Lepus), the equid (Eurygnathohippus),^[15] rhinoceroses (Ceratotherium and Diceros),^[16] old world primates (Parapapio, Theropithecus, and Cercopithecoides), proboscideans (the deinothere Deinotherium and elephants Elephas, Loxodonta, and Mammuthus) ^[17][18][19] old world porcupines (Hystrix and Xenohystrix),^[20] murid rodents (Gerbilliscus, Acomys, Golunda, Oenomys, Praomys, Saidomys, Millardia, and Mus),^[21] the spalacid Tachyoryctes, a squirrel indet., and an aardvark species. Taxons within other classes are present within the Hadar Formation as well, such as birds (Plectropterus, Balearica, Anhinga, and Struthio) and reptiles (Crocodylus, Python, Varanus, and Bitis).^{[22][23][24][25][26][27][28][29]}

Color key Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon		Notes Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Mammals

Artiodactyls

Bovidae

Bovids of the Hadar Formation
Taxa	Species	Presence	Material	Notes	Images
Aepyceros	A. datoadeni	Kada Hadar Member at Hadar	Near-complete skull lacking parts of horn cores (AL 787-1 KH1)[9]	An impala
Beatragus	B. sp.		Detached braincase with two horn cores[9]	A hirola
Budorcas	B. churcheri[30]	Sida Hakoma Member.[9]	Complete skull with horns (AL 136-5 DD2)[9]	An extinct takin
Damalops	D. sidihakomai[31]	Sidi Hakoma Member	AL 208–7, a skull with horn cores, right P4–M3, and left M2–3.	An extinct genus of Alcelaphinae
Damalborea	D. elisabethae	Basal and Sidi Hakoma members[9]	A skull with horn cores (AL 208-07 SH3)[9]	An extinct genus of Alcelaphinae
	D. grayi	Denen Dora and Kada Hadar members[9]	Multiple postcranial fragments, such as horn cores, maxillae, and mandibles[9]
Gazella	G. harmonae	Kada Hadar Member at Hadar[9]	Skull remains, such as isolated teeth, maxillae, frontlets, and occipital bones (AL 444-16)[9]	Extinct relatives of modern gazelles
	G. cf. janenschi	Denen Dora Member	Horn cores (AL 302-6 DD)[9]
	G. cf. praethomsoni	Denen Dora and Kada Hadar members	Few Horn core specimens[9]
Hippotragini	Praedamalis deturi	Kada Hadar, Sida Hakoma, and Denen Dora members at Hadar	Multiple specimens based on horn cores and lower teeth[9]	Ancestor of modern oryx
Kobus	K. hadarensis	Sidi Hakoma, Kada Hadar and Denen Dora member		Extinct relatives of antelopes
	K. oricornus	Denen Dora and Kada Hadar members	Several specimens of braincase and horn core[9]
Madoqua	M. sp.			Relative of dik-dik
Raphicerus	R. sp.	Kada Hadar and Sidi Hakoma members	Mandibles and horn cores[9]	Relative of Neotragini
Parmularius	P. pachyceras	Sidi Hakoma and Kada Hadar members[9]	Braincases and horn cores[9]	Large extinct alcelphines related to topis and hartebeests
Pelorovis	P. sp.
Tragelaphus	T. lockwoodi	Basal and Sidi Hakoma members	Braincase with complete horn cores (AL 142-3 SH2)[9]	Extinct relatives of spiral-horned antelopes
	T. rastafari	Basal, Sidi Hakoma, Denen Dora, and Kada Hadar members	Several horn core specimens
Ugandax	U. coryndonae	Denen Dora and Sidi Hakoma members at Hadar	Complete partial skull and horns (AL 194-1 DD1)[9]	Ancestor of Cape buffalo

Giraffidae

Giraffids of the Hadar Formation
Taxa	Species	Presence	Material	Notes	Images
Giraffa	G. jumae	Sidi Hakoma and Denen Dora members	Partial teeth, vertebrae, ossicones, limb bones, and mandibles[24]	Extinct relatives of modern giraffe
	G. stillei	Sidi Hakoma and Denen Dora members	Partial teeth, ossicones, limb bones, and mandibles[24]
Sivatherium	S. maurusium	Denen Dora, Kada Hadar, and Sidi Hakoma members	Partial mandibles and horns[24]	Okapi-like giraffid

Hippopotamidae

Hippopotamids of the Hadar Formation
Taxa	Species	Presence	Material	Notes	Images
Hexaprotodon	H. protoamphibius	Denen Dora Member	Partial skull and teeth	Extinct relatives of modern pygmy hippo
	H. coryndoni	Sidi Hakoma Member[28]	Partial skull and teeth
Hippopotamus	H. afarensis	Basal, Sidi Hakoma, Kada Hadar, and Denen Dora members[28]	Complete postcranial skull and mandibles	Extinct subspecies related to common hippopotamus, formally named Trilobophorus afarensis

Suidae

Suids of the Hadar Formation
Taxa	Species	Presence	Material	Notes	Images
Kolpochoerus	K. afarensis	Kada Hadar, Sidi Hakoma, and Denen Dora members[11]	Postcranial skulls, teeth fragments, and mandibles	Extinct relative of the pig family
Notochoerus	N. eulius	Kada Hadar, Lower and Upper Sidi Hakoma, and Denen Dora members[11]	Postcranial skull, teeth, and mandibles	A Tetraconodontinae pig.
Nyanzachoerus	N. kanamensis	Basal and Sidi Hakoma members[28]	Complete cranium, mandibles, and dentition	A Tetraconodontinae pig.
	N. pattersoni	Basal, Lower and Upper Sidi Hakoma, and Denen Dora members[11]	Complete skulls, mandibles, and dentition[11]

Carnivorans

Canidae

Canids of the Hadar Formation
Taxa	Species	Presence	Material	Notes	Images
Nyctereutes	N. lockwoodi	Sidi Hakoma and Denen Dora members at Dikika[23]	Nearly complete skull (DIK-31-1)[32]	A raccoon dog

Felidae

Felids of the Hadar Formation
Taxa	Species	Presence	Material	Notes	Images
Dinofelis	D. aronoki	Kada Hadar Member[12]	Postcranial member: distal radius (AL-363-20)[12]	A machairodontine felid
	D. petteri	Sidi Hakoma and Denen Dora members[12]	Postcranial member: partial humerus (AL 168-30), proximal ulna (AL 262-9), and right astragalus (Al 173-11)[12]
Felis	F. sp.	Kada Hadar, Sidi Hakoma, and Denen Dora members		A small cat relative
Homotherium	H. hadarensis	Denen Dora Member[23]	Complete cranium skull, mandible fragments (DIK-96-1), teeth, and forelimbs[23]	A machairodontine felid
Megantereon	M. sp.	Kada Hadar, Sidi Hakoma, and Denen Dora members		A machairodontine felid
Leptailurus	L. sp.			A serval cat
Panthera	P. sp.	Sidi Hakoma Member		Relatives of lions

Herpestidae

Herpestids of the Hadar Formation
Taxa	Species	Presence	Material	Notes	Images
Herpestes	H. sp.	Dikika site	Tooth fragments	A mongoose

Hyaenidae

Zdroj:https://en.wikipedia.org?pojem=Hadar_Formation
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Hyaenids of the Hadar Formation
Taxa	Species	Presence	Material	Notes	Images
Chasmaporthetes	C. sp.	Sidi Hakoma and Denen Dora members at Hadar[13]		A hunting hyena
Crocuta	C. dietrichi	Sidi Dakoma , Denen Dora, and Basal members at Hadar[13]	Fragmented mandibles (DIK-32-1)[23][13]	Extinct relatives of modern hyena
	C. eturono	Kada Hadar Member	Partial maxilla (DIK-73-1)[23]
Hyaena	H. sp.
Ikelohyaena	I. abronia	Sidi Hakoma Member at Hadar[13]		Early member of the Parahyaena lineage and the earliest close relative of the modern striped hyena