AL 333

Last updated March 27, 2022

AL 333, commonly referred to as the "First Family", is a collection of prehistoric hominid teeth and bones. Discovered in 1975 by Donald Johanson's team in Hadar, Ethiopia, the "First Family" is estimated to be about 3.2 million years old, and consists of the remains of at least thirteen individuals of different ages.^[1] They are generally thought to be members of the species Australopithecus afarensis. There are multiple theories about the hominids' cause of death and some debate over their species and sexual dimorphism.

Discovery

In the late 1960s, the French paleoanthropologist Maurice Taieb started geological exploration of the relatively unexplored area of Ethiopia known as the Afar Triangle, located in the north of the country. Also known as the Danakil depression or Afar depression, this triangle is the lowest point in Ethiopia and one of the lowest in Africa. In 1972, Taieb invited Yves Coppens, a French paleontologist, Jon Kalb, an American geologist, and Donald Johanson, an American anthropologist, to survey the region in order to appraise the area's field exploration potential. They soon settled on working in the Hadar Formation, a sedimentary geological formation within the region. The four men established the International Afar Research Expedition (IARE), with Johanson in charge of the paleoanthropology aspect of the expedition.^[2]^{: 466–468}

Historically, the Afar Triangle had been unexplored because it was remote and inhospitable. However, the IARE chose to explore the region for other reasons. The geological sequence of the Hadar Formation consists of nearly 200 meters of strata, or rock layers, which span a significant geological time. The sediment was also fossil-rich and often preserved partial skeletons of animals, implying that the researchers could potentially recover well-preserved and more complete fossils from the environment. Furthermore, the area had feldspars and volcanic glass that would be valuable for chronometric dating.^[2]^: 467

From 1973 to 1977, the IARE campaigns resulted in the discovery of about 250 hominid fossils.^[2]^{: 466–468} The most famous of the Hadar discoveries is Lucy, the most complete A. afarensis skeleton that has been discovered. However, in 1975, this same formation also witnessed the discovery of numerous remains from another site, AL 333. These remains became known as the "First Family," and represent at least thirteen different individuals, both adults and children. The recovery of these 216 hominid specimens is unique in African paleoanthropology, since the close proximity of the different fossils suggests that these were individuals who might have lived in a group or been part of the same family.^[2]^{: 471–472}

Characteristics of findings

Of the 216 specimens, 197 were surface finds, and 19 were found within 80 cm in the ground, suggesting a common time of death. Further visits to AL 333 resulted in the discovery of 23 additional postcranial and 3 mandibular and dental specimens. This increased the estimate from 13 to at least 17 individuals (9 adults, 3 adolescents, and 5 young children). The fossils lacked extensive weathering.^[2]^{: 471–472}

In 2000, a complete fossil of the fourth metatarsal was recovered from AL 333. The morphology of this bone suggests that A. afarensis had transverse and longitudinal foot arches and therefore also had a very human-like bipedal gait.^[3]

Dating

The discovery of all of the fossils at AL 333 aligned close together in one geological stratum is an obvious sign that they died at about the same time. But absolute dating had to be used to ascertain that time. Because the specimens were found between two layers of volcanic ash, potassium-argon dating was used. Potassium-argon dating measures the ratio of radioactive potassium and the argon it decays into. It is ideal for dating volcanic material. In the case of AL 333, this method yielded an age of 3.18-3.21 million years.^[4]

Debate

Cause of death

The unique grouping of such a large number of individuals in the same place and at virtually the same time has led to much speculation over the cause of death. One popular theory was a flash flood, but more detailed study of the geological formation of the site has largely discredited this idea.^[2]^: 472 An alternative theory is predation by large cats. This is partially supported by the absence of particular bone types and what may be damage to the fossils from a carnivore.^[2]^: 472 However, damage to the fossils from predation is disputed. If a predator did kill the hominids, it would also mean that the bodies were likely accumulated at the site and not all killed at once.^[5] An additional theory suggested was food poisoning, but Johanson doubts this because of the hominids' vegetarian diet.^[5] In the ITV television series Primeval, it is shown that time-travelling scientist Helen Cutter poisoned the group in an effort to prevent humanity from evolving, thus retaining the Earth's natural and proper beauty.

Species

Many doubts among the archaeological community have been expressed about whether or not the fossils of the "First Family" belong to a single species. The fact that the fossils consist of thirteen individuals all dating to the same time suggests that they are the same species. However, some believe that this is simply coincidence.^[6]

In an effort to solve this debate, archaeologists have extensively studied the size of the bones. The sizes of the largest bones found such as humeri and femora were compared. Although they measured different bones, all of the measurements could be used to estimate the size of the femoral head. Then, these measurements were compared to the femoral head of Lucy. The researchers believe that, like Lucy, the fossils probably belong to the species Australopithecus afarensis.^[6]

Sexual dimorphism

Once the individuals of the "First Family" were determined to be the same species, they became very useful to study the biological phenomenon of sexual dimorphism. The fossils of the 13-17 individuals are mostly jaws and teeth, but the few humeri and femora could be used to differentiate males and females. Early testing displayed results that strayed far from previous beliefs. The test results showed that A. afarensis had similar dimorphism to modern humans. During these early tests, it was assumed that the fossils represented a variety of males and females. However, some paleoanthropologists disagree with this, believing that although the size of the bones vary at AL 333, the variation is due to age and not the sex of the individuals. In order to give more insight about the sexual dimorphism of A. afarensis, the fossil bones from AL 333 were compared to other sites that contained remains of females. These tests show a level of sexual dimorphism comparable to gorillas, meaning that males were significantly larger than females.^[7]

Related Research Articles

Australopithecus is a genus of early hominins that existed in Africa during the Late Pliocene and Early Pleistocene. The genera Homo emerged within Australopithecus, as sister to e.g. Australipitecus sediba. Also the genera Paranthropus, and Kenyanthropus emerged within the Australopithecus. Australopithecus is a member of the subtribe Australopithecina, which also includes Ardipithecus, though the term "australopithecine" is sometimes used to refer only to members of Australopithecus. Species include A. garhi, A. africanus, A. sediba, A. afarensis, A. anamensis, A. bahrelghazali and A. deyiremeda. Debate exists as to whether some Australopithecus species should be reclassified into new genera, or if Paranthropus and Kenyanthropus are synonymous with Australopithecus, in part because of the taxonomic inconsistency.

Donald Carl Johanson is an American paleoanthropologist. He is known for discovering, with Yves Coppens and Maurice Taieb, the fossil of a female hominin australopithecine known as "Lucy" in the Afar Triangle region of Hadar, Ethiopia.

Australopithecus afarensis is an extinct species of australopithecine which lived from about 3.9–2.9 million years ago (mya) in the Pliocene of East Africa. The first fossils were discovered in the 1930s, but major fossil finds would not take place until the 1970s. From 1972 to 1977, the International Afar Research Expedition—led by anthropologists Maurice Taieb, Donald Johanson and Yves Coppens—unearthed several hundreds of hominin specimens in Hadar, Ethiopia, the most significant being the exceedingly well-preserved skeleton AL 288-1 ("Lucy") and the site AL 333. Beginning in 1974, Mary Leakey led an expedition into Laetoli, Tanzania, and notably recovered fossil trackways. In 1978, the species was first described, but this was followed by arguments for splitting the wealth of specimens into different species given the wide range of variation which had been attributed to sexual dimorphism. A. afarensis probably descended from A. anamensis and is hypothesised to have given rise to Homo, though the latter is debated.

Paleoanthropology or paleo-anthropology is a branch of paleontology and anthropology which seeks to understand the early development of anatomically modern humans, a process known as hominization, through the reconstruction of evolutionary kinship lines within the family Hominidae, working from biological evidence and cultural evidence.

Hadar is a paleontological site 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.

Australopithecus anamensis is a hominin species that lived approximately between 4.2 and 3.8 million years ago and is the oldest known Australopithecus species, living during the Plio-Pleistocene era.

Australopithecus garhi is a species of australopithecine from the Bouri Formation in the Afar Region of Ethiopia 2.6–2.5 million years ago (mya) during the Early Pleistocene. The first remains were described in 1999 based on several skeletal elements uncovered in the three years preceding. A. garhi was originally considered to have been a direct ancestor to Homo and the human line, but is now thought to have been an offshoot. Like other australopithecines, A. garhi had a brain volume of 450 cc (27 cu in); a jaw which jutted out (prognathism); relatively large molars and premolars; adaptations for both walking on two legs (bipedalism) and grasping while climbing (arboreality); and it is possible that, though unclear if, males were larger than females. One individual, presumed female based on size, may have been 140 cm tall.

The Afar Region, formerly known as Region 2, is a regional state in northeastern Ethiopia and the homeland of the Afar people. Its capital is the planned city of Semera, which lies on the paved Awash–Assab highway.

The Gawis cranium is a portion of a fossil hominin skull discovered on February 16, 2006 near the drainage of Gawis, a tributary of the Awash River in the Afar Depression, Ethiopia. Despite the presence of volcanic ash layers that are key to dating, the cranium is only generally dated between 200,000 and 500,000 years ago due to taphonomic issues.

Aramis is a village and archaeological site in north-eastern Ethiopia, where remains of Australopithecus and Ardipithecus have been found. The village is located in Administrative Zone 5 of the Afar Region, which is part of the Afar Sultanate of Dawe, with a latitude and longitude of 10°30′N40°30′E, and is part of the, Carri Rasuk, Xaale Faagê Daqaara.

Yohannes Haile-SelassieAmbaye is an Ethiopian paleoanthropologist. An authority on pre-Homo sapiens hominids, he particularly focuses his attention on the East African Rift and Middle Awash valleys. He was curator of Physical Anthropology at the Cleveland Museum of Natural History from 2002 until 2021, and now is serving as the director of the Arizona State University Institute of Human Origins. Since founding the institute in 1981, he has been the third director after Donald Johanson and William Kimbel

AL 200-1 is the fossilized upper palate and teeth of the species Australopithecus afarensis, estimated to be 3.0-3.2 million years old. Its characteristics are an ape-like arrangement of teeth including spatulate incisors and a gap between the canines and outside incisors.

AL 129-1 is a fossilized knee joint of the species Australopithecus afarensis. It was discovered in Hadar, Ethiopia by Donald Johanson in November 1973.

AL 288-1, commonly known as Lucy, is a collection of several hundred pieces of fossilized bone representing 40 percent of a female of the hominin species Australopithecus afarensis. In Ethiopia, the assembly is also known as Dinkinesh, which means "you are marvelous" in Amharic. Lucy was discovered in 1974 in Africa, at Hadar, a site in the Awash Valley of the Afar Triangle in Ethiopia, by paleoanthropologist Donald Johanson of the Cleveland Museum of Natural History.

"Little Foot" is the nickname given to a nearly complete Australopithecus fossil skeleton found in 1994–1998 in the cave system of Sterkfontein, South Africa.

Selam (<i>Australopithecus</i>) Hominin fossil

Selam (DIK-1/1) is the fossilized skull and other skeletal remains of a three-year-old Australopithecus afarensis female hominin, whose bones were first found in Dikika, Ethiopia in 2000 and recovered over the following years. Although she has often been nicknamed Lucy's baby, the specimen has been dated at 3.3 million years ago, approximately 120,000 years older than "Lucy".

The Dikika is an area of the Afar Region of Ethiopia where the hominin fossil named Selam was found. Dikika is located in Mille woreda.

Maurice Taieb was a French geologist and paleoanthropologist. He discovered the Hadar formation, recognized its potential importance to paleoanthropology and founded the International Afar Research Expedition (IARE). This enabled co-director Donald Johanson to discover an early hominin fossil, the 3.2-million-year-old Australopithecine Lucy in the Awash Valley of Ethiopia's Afar Depression.

The Bouri Formation is a sequence of sedimentary deposits that is the source of australopithecine and Homo fossils, artifacts, and bones of large mammals with cut marks from butchery with tools by early hominins. It is located in the Middle Awash Valley, in Ethiopia, East Africa, and is a part of the Afar Depression that has provided rich human fossil sites such as Gona and Hadar.

The Middle Awash Project is an international research expedition conducted in the Afar region of Ethiopia with the goal of determining the origins of humanity. The project has the approval of the Ethiopian Culture Ministry and a strong commitment to developing Ethiopian archaeology, paleontology and geology research infrastructure. This project has discovered over 260 fossil specimens and over 17,000 vertebrate fossil specimens to date ranging from 200,000 to 6,000,000 years in age. Researchers have discovered the remains of four hominin species, the earliest subspecies of homo sapiens as well as stone tools. All specimens are permanently held at the National Museum of Ethiopia, where the project’s laboratory work is conducted year round.

References

↑ Switek, Brian (10 January 2011). "What Killed the Hominins of AL 333?". Wired . Retrieved 12 April 2016.
1 2 3 4 5 6 7 Johanson, Donald C. (2004). "Lucy, Thirty Years Later: An Expanded View of Australopithecus afarensis". Journal of Anthropological Research . 60 (4): 465–486. doi:10.1086/jar.60.4.3631138. S2CID 159745450.
↑ Ward, Carol V.; Kimbel, William H. & Johanson, Donald C. (11 February 2011). "Complete Fourth Metatarsal and Arches in the Foot of Australopithecus Afarensis". Science . 331 (6018): 750–753. Bibcode:2011Sci...331..750W. doi:10.1126/science.1201463. PMID 21311018. S2CID 206531695.
↑ Johanson, Donald C.; Edgar, Blake (1996). From Lucy to Language. New York: Simon & Schuster. p. 126. ISBN 978-0-68481-023-2.
1 2 Smillie, Shaun (3 October 2008). "SA academic called on to solve fossil mystery". The Star . p. 6.
1 2 Gordon, Adam D.; Green, David J. & Richmond, Brian G. (2008). "Strong postcranial size dimorphism in Australopithecus afarensis: Results from two new resampling methods for multivariate data sets with missing data" (PDF). American Journal of Physical Anthropology . 135 (3): 311–328. doi:10.1002/ajpa.20745. PMID 18044693.
↑ Plavcan, J. Michael; Lockwood, Charles A.; Kimbel, William H.; Lague, Michael R. & Harmon, Elizabeth H. (March 2005). "Sexual dimorphism in Australopithecus afarensis revisited: How strong is the case for a human-like pattern of dimorphism?". Journal of Human Evolution . 48 (3): 313–320. doi:10.1016/j.jhevol.2004.09.006. PMID 15737396.

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.

[1] Switek, Brian (10 January 2011). "What Killed the Hominins of AL 333?". Wired . Retrieved 12 April 2016.

[Johanson,_D._2004-2] 1 2 3 4 5 6 7 Johanson, Donald C. (2004). "Lucy, Thirty Years Later: An Expanded View of Australopithecus afarensis". Journal of Anthropological Research . 60 (4): 465–486. doi:10.1086/jar.60.4.3631138. S2CID 159745450.

[3] Ward, Carol V.; Kimbel, William H. & Johanson, Donald C. (11 February 2011). "Complete Fourth Metatarsal and Arches in the Foot of Australopithecus Afarensis". Science . 331 (6018): 750–753. Bibcode:2011Sci...331..750W. doi:10.1126/science.1201463. PMID 21311018. S2CID 206531695.

[4] Johanson, Donald C.; Edgar, Blake (1996). From Lucy to Language. New York: Simon & Schuster. p. 126. ISBN 978-0-68481-023-2.

[iol.co.za-5] 1 2 Smillie, Shaun (3 October 2008). "SA academic called on to solve fossil mystery". The Star . p. 6.

[Gordon,_A._D._2007-6] 1 2 Gordon, Adam D.; Green, David J. & Richmond, Brian G. (2008). "Strong postcranial size dimorphism in Australopithecus afarensis: Results from two new resampling methods for multivariate data sets with missing data" (PDF). American Journal of Physical Anthropology . 135 (3): 311–328. doi:10.1002/ajpa.20745. PMID 18044693.

[7] Plavcan, J. Michael; Lockwood, Charles A.; Kimbel, William H.; Lague, Michael R. & Harmon, Elizabeth H. (March 2005). "Sexual dimorphism in Australopithecus afarensis revisited: How strong is the case for a human-like pattern of dimorphism?". Journal of Human Evolution . 48 (3): 313–320. doi:10.1016/j.jhevol.2004.09.006. PMID 15737396.

[1]

[2]

[3]

[4]

[5]

[6]

[7]