KNM ER 406 is an almost complete fossilized skull of the species Paranthropus boisei.[1] It was discovered in Koobi Fora, Kenya by Richard Leakey and H. Mutua in 1969.[2] This species is grouped with the Australopitecine genus, Paranthropus boisei because of the robusticity of the skull and the prominent characteristics. This species was found well preserved with a complete cranium but lacking dentition. He was known for his robust cranial features that showed the signs of adaptation of the ecological niches. The big chewing muscles attached to the sagittal crest are traits of this adaptation.[3]
Following a three-month expedition funded by the National Museums of Kenya, Richard Leakey and H. Mutua spent the summer of 1969 in northern Kenya. This expedition along with the field work three months prior to this project was possible with the financial assistance from the Kenyan Government. During this expedition, there were two specimens that have similar characteristics as seen in the robust KNM-ER 406. The two specimens are Demi-cranium KNM-ER 732 and KNM-ER 407. These two specimens were also robust, but the skulls were considered more gracile. The smaller skulls are evidence that sexual dimorphism was the reason for the size difference. Consistent evidence of Lower Pleistocene hominids supports that there was a variation in size of the Australopithecus in East Rudolf, and not a separate species.[4]
With the occipital only being present the morphology could not be confirmed, but the KNM-ER 406 and the other fossil found a mile North of the site are consistent with fossils found in Olduvai. It has been accepted that they are Australopithecus boisei and it's also been accepted that the A. boisei was not a tool maker.[4]
Another species, called Homo ergaster was discovered and dated the same age as A. Boisei 1.7 million years ago. In 1975 this species was found in northern Kenya, Koobi Fora by Bernard Ngeneo. The same age of 1.7 million years ago means that different species were on the scene in Africa at the same time. Yes, they coexisted. It's known that a species can survive when they inhabit a specific ecological niche. The morphology was different because of the resources they consumed. The Homo ergaster hunted and ate softer foods and more meat. His skull looked more like modern humans. But, A. Boisei’s skull was robust and had large temporals muscles that helped crush nuts and hard plants. It's important to note that these two species coexisted.[5]
Anatomyedit
Cranial features and brain size
It is an adult male with an estimated cranial capacity of 510 cc and age of 1.7 million years.
Compared to the modern human and the Homo ergaster the A. boisei had a cranial capacity of 510 cc, a much smaller brain then modern humans who have a cranial capacity of 1200-1400 cc. He had striking robusticity, projecting glabella, and a well developed sagittal crest. There are feature differences of the sagittal crest in the KNM-ER 406 and the robust male gorillas and chimpanzees. Roughness appears in the sagittal crest and its located further back by the nuchal crest of gorillas and apes. The KNM-ER 406 sagittal crest is situated near the frontal bone and the highest point of the sagittal crest is located more medially. The development of the robusticity comes from the anterior part of the temporals muscles. As a result of this massiveness size of temporals muscles KNM-ER 406 shows presents of shallow orbits.[6] This species is suggested to be male and his features are the same as Paranthropus boisei and the OH 5.[7] This specimen is perhaps the most impressive skull found.
^"KNM-ER 406". Archaeology Info. Retrieved 6 March 2012.
^"Smithsonian Institution's Human Origins program: KNM-ER 406". Smithsonian Institution. Retrieved 6 March 2012.
^Wood, Bernard; Constantino, Paul (2007). "Paranthropus boisei: Fifty years of evidence and analysis". American Journal of Physical Anthropology. 134 (S45): 106–132. doi:10.1002/ajpa.20732. ISSN 1096-8644. PMID 18046746.
^ abLeakey, R. E. F. (1970-04-18). "New Hominid Remains and Early Artefacts from Northern Kenya: Fauna and Artefacts from a New Plio-Pleistocene Locality near Lake Rudolf in Kenya". Nature. 226 (5242): 223–224. Bibcode:1970Natur.226..223L. doi:10.1038/226223a0. ISSN 0028-0836. PMID 5437512. S2CID 3118920.
^Sáez, Roberto (2016-03-10). "Two very different specimens that coexisted: P. boisei ER 406 and H. ergaster ER 3733". Nutcracker Man (in European Spanish). Retrieved 2020-05-23.
^Rak, Yoel (1978). "The functional significance of the squamosal suture in Australopithecus boisei". American Journal of Physical Anthropology. 49 (1): 71–78. doi:10.1002/ajpa.1330490111. ISSN 1096-8644. PMID 98055.
^Sáez, Roberto (2016-03-10). "Two very different specimens that coexisted: P. boisei ER 406 and H. ergaster ER 3733". Nutcracker Man (in European Spanish). Retrieved 2020-05-23.
almost, complete, fossilized, skull, species, paranthropus, boisei, discovered, koobi, fora, kenya, richard, leakey, mutua, 1969, this, species, grouped, with, australopitecine, genus, paranthropus, boisei, because, robusticity, skull, prominent, characteristi. KNM ER 406 is an almost complete fossilized skull of the species Paranthropus boisei 1 It was discovered in Koobi Fora Kenya by Richard Leakey and H Mutua in 1969 2 This species is grouped with the Australopitecine genus Paranthropus boisei because of the robusticity of the skull and the prominent characteristics This species was found well preserved with a complete cranium but lacking dentition He was known for his robust cranial features that showed the signs of adaptation of the ecological niches The big chewing muscles attached to the sagittal crest are traits of this adaptation 3 KNM ER 406Catalog no KNM ER 406SpeciesParanthropus boiseiAge1 7 million years Lower PleistocenePlace discoveredKoobi Fora KenyaDate discovered1969Discovered byRichard Leakey and H Mutua Contents 1 Discovery and classification 2 Anatomy 3 See also 4 References 5 External linksDiscovery and classification editFollowing a three month expedition funded by the National Museums of Kenya Richard Leakey and H Mutua spent the summer of 1969 in northern Kenya This expedition along with the field work three months prior to this project was possible with the financial assistance from the Kenyan Government During this expedition there were two specimens that have similar characteristics as seen in the robust KNM ER 406 The two specimens are Demi cranium KNM ER 732 and KNM ER 407 These two specimens were also robust but the skulls were considered more gracile The smaller skulls are evidence that sexual dimorphism was the reason for the size difference Consistent evidence of Lower Pleistocene hominids supports that there was a variation in size of the Australopithecus in East Rudolf and not a separate species 4 With the occipital only being present the morphology could not be confirmed but the KNM ER 406 and the other fossil found a mile North of the site are consistent with fossils found in Olduvai It has been accepted that they are Australopithecus boisei and it s also been accepted that the A boisei was not a tool maker 4 Another species called Homo ergaster was discovered and dated the same age as A Boisei 1 7 million years ago In 1975 this species was found in northern Kenya Koobi Fora by Bernard Ngeneo The same age of 1 7 million years ago means that different species were on the scene in Africa at the same time Yes they coexisted It s known that a species can survive when they inhabit a specific ecological niche The morphology was different because of the resources they consumed The Homo ergaster hunted and ate softer foods and more meat His skull looked more like modern humans But A Boisei s skull was robust and had large temporals muscles that helped crush nuts and hard plants It s important to note that these two species coexisted 5 Anatomy editCranial features and brain sizeIt is an adult male with an estimated cranial capacity of 510 cc and age of 1 7 million years Compared to the modern human and the Homo ergaster the A boisei had a cranial capacity of 510 cc a much smaller brain then modern humans who have a cranial capacity of 1200 1400 cc He had striking robusticity projecting glabella and a well developed sagittal crest There are feature differences of the sagittal crest in the KNM ER 406 and the robust male gorillas and chimpanzees Roughness appears in the sagittal crest and its located further back by the nuchal crest of gorillas and apes The KNM ER 406 sagittal crest is situated near the frontal bone and the highest point of the sagittal crest is located more medially The development of the robusticity comes from the anterior part of the temporals muscles As a result of this massiveness size of temporals muscles KNM ER 406 shows presents of shallow orbits 6 This species is suggested to be male and his features are the same as Paranthropus boisei and the OH 5 7 This specimen is perhaps the most impressive skull found nbsp Paranthropus boisei KNM ER 406 actual skullSee also editList of fossil sites with link directory List of hominina hominid fossils with images References edit KNM ER 406 Archaeology Info Retrieved 6 March 2012 Smithsonian Institution s Human Origins program KNM ER 406 Smithsonian Institution Retrieved 6 March 2012 Wood Bernard Constantino Paul 2007 Paranthropus boisei Fifty years of evidence and analysis American Journal of Physical Anthropology 134 S45 106 132 doi 10 1002 ajpa 20732 ISSN 1096 8644 PMID 18046746 a b Leakey R E F 1970 04 18 New Hominid Remains and Early Artefacts from Northern Kenya Fauna and Artefacts from a New Plio Pleistocene Locality near Lake Rudolf in Kenya Nature 226 5242 223 224 Bibcode 1970Natur 226 223L doi 10 1038 226223a0 ISSN 0028 0836 PMID 5437512 S2CID 3118920 Saez Roberto 2016 03 10 Two very different specimens that coexisted P boisei ER 406 and H ergaster ER 3733 Nutcracker Man in European Spanish Retrieved 2020 05 23 Rak Yoel 1978 The functional significance of the squamosal suture in Australopithecus boisei American Journal of Physical Anthropology 49 1 71 78 doi 10 1002 ajpa 1330490111 ISSN 1096 8644 PMID 98055 Saez Roberto 2016 03 10 Two very different specimens that coexisted P boisei ER 406 and H ergaster ER 3733 Nutcracker Man in European Spanish Retrieved 2020 05 23 External links edit nbsp Media related to KNM ER 406 at Wikimedia Commons nbsp This prehistoric hominin related article is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title KNM ER 406 amp oldid 1187031730, wikipedia, wiki, book, books, library,
