Misplaced Pages

Aquatic ape hypothesis

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.

This is an old revision of this page, as edited by ජපස (talk | contribs) at 20:31, 30 March 2017 (Reverted edits by Chris55 (talk) to last version by 9SGjOSfyHJaQVsEmy9NS). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Revision as of 20:31, 30 March 2017 by ජපස (talk | contribs) (Reverted edits by Chris55 (talk) to last version by 9SGjOSfyHJaQVsEmy9NS)(diff) ← Previous revision | Latest revision (diff) | Newer revision → (diff)
This article may present fringe theories, without giving appropriate weight to the mainstream view and explaining the responses to the fringe theories. Please help improve it or discuss the issue on the talk page. (February 2017) (Learn how and when to remove this message)
This article possibly contains original research. Please improve it by verifying the claims made and adding inline citations. Statements consisting only of original research should be removed. (February 2017) (Learn how and when to remove this message)
Elaine Morgan, popularizer of the aquatic ape hypothesis. Morgan promoted the idea through the publication of the following popular-level books between 1972 and 2008: The Descent of Woman, The Aquatic Ape, The Scars of Evolution, The Descent of the Child, The Aquatic Ape Hypothesis, and The Naked Darwinist.

The aquatic ape hypothesis (AAH), also referred to as aquatic ape theory (AAT) and more recently the waterside model, is the idea that the ancestors of modern humans were more aquatic in the past. The hypothesis in its present form was proposed by the marine biologist Alister Hardy in 1960 who argued that a branch of apes was forced by competition from life in the trees to hunt for food such as shellfish on the sea shore and that this explained many characteristics such as man's upright posture. This proposal was noticed by Elaine Morgan, a scriptwriter, who objected to the male image of the "mighty hunter" being presented in popular anthropological works by Raymond Dart, Desmond Morris and others. While her 1972 book The Descent of Woman was very popular with the public, it attracted no attention from scientists, who saw no way of testing assertions about soft body parts and human habits in the distant past.

Morgan removed the feminist polemic in several later books, and her ideas were discussed at a 1987 conference devoted to the idea. Her 1990 book Scars of Evolution received some favorable reviews, but the thesis was subject to scathing criticism from the anthropologist John Langdon in 1997 who characterized it as an "umbrella hypothesis" and argued that the hypothesis is not more parsimonious than simply rejecting the hypothesis.

In the last 15 years, one corollary of the hypothesis has received some support within the scientific community: that at some point in the last five million years humans became dependent on essential fatty acids and iodine, which are found in abundance in sea resources. Efficient function of the human brain requires these nutrients.

The entirety of the "aquatic ape" proposal remains highly controversial, and is more popular with the lay public than with scientists.

History

Hominin timeline
This box:
−10 —–−9 —–−8 —–−7 —–−6 —–−5 —–−4 —–−3 —–−2 —–−1 —–0 —MiocenePliocenePleistoceneHomininiNakalipithecusSamburupithecusOuranopithecus
(Ou. turkae)
(Ou. macedoniensis)ChororapithecusOreopithecusSivapithecusSahelanthropusGraecopithecusOrrorin(O. praegens)
(O. tugenensis)Ardipithecus(Ar. kadabba)(Ar. ramidus)Australopithecus
(Au. africanus)
(Au. afarensis)
(Au. anamensis)H. habilis
(H. rudolfensis)
(Au. garhi)H. erectus
(H. antecessor)
(H. ergaster)
(Au. sediba)H. heidelbergensisHomo sapiensNeanderthalsDenisovans 
←Earlier apes
←Gorilla split
←Chimpanzee split
←Earliest bipedal
←Earliest sign of Ardipithecus
←Earliest sign of Australopithecus
←Earliest stone tools
←Earliest sign of
Homo
←Dispersal beyond Africa
←Earliest language
←Earliest fire / cooking
←Earliest rock art
←Earliest clothes
←Modern humans
H o m i n i d sP a r a n t h r o p u s
(million years ago)

The German pathologist Max Westenhöfer (1871–1957) discussed in 1942 various human characteristics (hairlessness, subcutaneous fat, the regression of the olfactory organ, webbed fingers, direction of the body hair etc.) that could have derived from an aquatic past, quoting several other authors who had made similar speculations. As he did not believe human beings were apes, he believed this might have been during the Cretaceous, contrary to what is possible given the geologic and evolutionary biology evidence available at the time. He stated: "The postulation of an aquatic mode of life during an early stage of human evolution is a tenable hypothesis, for which further inquiry may produce additional supporting evidence." He later abandoned the concept.

Independently of Westenhöfer's writings, the marine biologist Alister Hardy had since 1930 also hypothesized that humans may have had ancestors more aquatic than previously imagined, although his work, unlike Westenhöfer's, was rooted in the Darwinian consensus. Out of an apparent abundance of caution, Hardy delayed reporting the hypothesis for some thirty years. After he had become a respected academic and knighted for contributions to marine biology, Hardy finally voiced his thoughts in a speech to the British Sub-Aqua Club in Brighton on 5 March 1960. Several national newspapers reported sensational presentations of Hardy's ideas, which he countered by explaining them more fully in an article in New Scientist on 17 March 1960: "My thesis is that a branch of this primitive ape-stock was forced by competition from life in the trees to feed on the sea-shores and to hunt for food, shellfish, sea-urchins etc., in the shallow waters off the coast."

The idea was generally ignored by the scientific community after the article was published. Some interest was received, notably from the geographer Carl Sauer whose views on the role of the seashore in human evolution "stimulated tremendous progress in the study of coastal and aquatic adaptations" inside marine archaeology. In 1967, the hypothesis was mentioned in The Naked Ape, a popular book by the zoologist Desmond Morris, who reduced Hardy's phrase "more aquatic ape-like ancestors" to the bare "aquatic ape", commenting that "despite its most appealing indirect evidence, the aquatic theory lacks solid support".

While traditional descriptions of 'savage' existence identified three common sources of sustenance: gathering of fruit and nuts, fishing and hunting, in the 1950s, the anthropologist Raymond Dart focused on hunting and gathering as the likely organizing concept of human society in prehistory, and hunting was the focus of the screenwriter Robert Ardrey's 1961 best-seller African Genesis. Another screenwriter, Elaine Morgan, responded to this bloodthirsty vision in her 1972 Descent of Woman, which parodied the conventional picture of "the Tarzanlike figure of the prehominid who came down from the trees, saw a grassland teeming with game, picked up a weapon and became a Mighty Hunter," and pictured a more peaceful scene of humans by the seashore. She took her lead from a section in Morris's 1967 book which referred to the possibility of an Aquatic Ape period in evolution, his name for the speculation by the biologist Alister Hardy in 1960. When it aroused no interest in the academic community, she dropped the feminist polemic and wrote a series of books–The Aquatic Ape (1982), The Scars of Evolution (1990), The Descent of the Child (1994) and The Aquatic Ape Hypothesis (1997)–which explored the issues in more detail.

The Hardy/Morgan hypothesis

Hardy's hypothesis as outlined in the New Scientist was:

My thesis is that a branch of this primitive ape-stock was forced by competition from life in the trees to feed on the sea-shores and to hunt for food, shell fish, sea-urchins etc., in the shallow waters off the coast. I suppose that they were forced into the water just as we have seen happen in so many other groups of terrestrial animals. I am imagining this happening in the warmer parts of the world, in the tropical seas where Man could stand being in the water for relatively long periods, that is, several hours at a stretch.

Hardy argued a number of features of modern humans are characteristic of aquatic adaptations. He pointed to human's lack of body hair as being analogous to the same lack seen in a number of other marine mammals, such as the whale and the hippopotamus, and noted the layer of Subcutaneous fat humans have which other apes lack. Additional features cited by Hardy include the location of the trachea in the throat rather than the nasal cavity, the human propensity for front-facing copulation, tears and Eccrine sweating. Hardy additionally posited that bipedalism evolved first as an aid to wading before becoming the usual means of human locomotion, and tool use evolved out of the use of rocks to crack open shellfish.

Morgan summed up her take on the hypothesis in 2011:

Waterside hypotheses of human evolution assert that selection from wading, swimming and diving and procurement of food from aquatic habitats have significantly affected the evolution of the lineage leading to Homo sapiens as distinct from that leading to Pan.

Reactions

This section may lend undue weight to certain ideas, incidents, or controversies. Please help improve it by rewriting it in a balanced fashion that contextualizes different points of view. (March 2017) (Learn how and when to remove this message)

Academics who have commented on the aquatic ape hypothesis include strident opponents (generally members of the community of academic anthropology) who reject almost all of the claims related to the hypothesis. Other academics have argued that the rejection of Hardy and Morgan is partially unfair given that other explanations which suffer from similar problems are not so stridently opposed. The first of two conferences was held at Valkenburg, Netherlands in 1987. Its 22 participants included academic proponents and opponents of the theory and several neutral observers headed by the anthropologist Vernon Reynolds of Oxford University. His summary at the end was:

Overall, it will be clear that I do not think it would be correct to designate our early hominid ancestors as 'aquatic'. But at the same time there does seem to be evidence that not only did they take to water from time to time but that the water (and by this I mean inland lakes and rivers) was a habitat that provided enough extra food to count as an agency for selection.

Silence and opposition

The AAH has received little attention from mainstream anthropologists and paleoanthropologists. It is not accepted as empirically supported by the scholarly community, and has been met with significant skepticism.

In a widely read 1997 critique, Langdon considered the AAH under the heading of an "umbrella hypothesis" and pointed that the difficulty of ever disproving such a thing meant that although the idea has the appearance of being a parsimonious explanation, it actually was no more powerful an explanation than the null hypothesis that human evolution is not peculiarly guided by interaction with bodies of water. Langdon argued that however popular the idea was with the public, the "umbrella" nature of the idea means that it cannot service as a proper scientific hypothesis. Langdon also objected to Morgan's blanket opposition to the "savannah hypothesis" which he took to be the "collective discipline of paleoanthropology". He observed that some anthropologists had regarded the idea as not worth the trouble of a rebuttal. In addition, the evidence cited by AAH proponents mostly concerned developments in soft tissue anatomy and physiology, whilst paleoanthropologists rarely speculated on evolutionary development of anatomy beyond the musculoskeletal system and brain size as revealed in fossils. After a brief description of the issues under 26 different headings, he produced a summary critique of these with mainly negative judgments. His main conclusion was that the AAH was unlikely ever to be disproved on the basis of comparative anatomy, and that the one body of data that could potentially disprove it was the fossil record.

Anthropologist John D. Hawks wrote that it is fair to categorize the AAH as pseudoscience because of social factors that inform it, particularly the personality-led nature of the hypothesis and the unscientific approach of its adherents. Physical anthropologist Eugenie Scott has described the aquatic ape hypothesis as an instance of "crank anthropology" akin to other pseudoscientific ideas in anthropology such as alien-human interbreeding and Bigfoot.

In The Accidental Species: Misunderstandings of Human Evolution (2013), the Nature editor Henry Gee remarked on how a seafood diet can aid in the development of the human brain. He nevertheless criticized the AAH because "it's always a problem identifying features that humans have now and inferring that they must have had some adaptive value in the past." Also "it's notoriously hard to infer habits from anatomical structures".

Popular support for the AAH has become an embarrassment to some anthropologists who want to explore the effects of water on human evolution without engaging with the AAH, which they consider "emphasizes adaptations to deep water (or at least underwater) conditions". Foley and Lahr suggest that "to flirt with anything watery in paleoanthropology can be misinterpreted", but argue "there is little doubt that throughout our evolution we have made extensive use of terrestrial habitats adjacent to fresh water, since we are, like many other terrestrial mammals, a heavily water-dependent species." But they allege that "under pressure from the mainstream, AAH supporters tended to flee from the core arguments of Hardy and Morgan towards a more generalized emphasis on fishy things."

Positive reactions as part of broader critiques of paleoanthropology

Philosopher Daniel Dennett, in his discussion of evolutionary philosophy, commented "During the last few years, when I have found myself in the company of distinguished biologists, evolutionary theorists, paleoanthropologists and other experts, I have often asked them to tell me, please, exactly why Elaine Morgan must be wrong about the aquatic theory. I haven’t yet had a reply worth mentioning, aside from those who admit, with a twinkle in their eyes, that they have also wondered the same thing." He challenged both Elaine Morgan and the scientific establishment in that "Both sides are indulging in adaptionist Just So stories". Along the same lines, historian Erika Lorraine Milam noted that independent of Morgan's work, certain standard explanations of human development in paleoanthropology have been roundly criticized for lacking evidence while being based on sexist assumptions. Anatomy lecturer Bruce Charlton gave Morgan's book Scars of Evolution an enthusiastic review in the British Medical Journal in 1991, calling it "exceptionally well written" and "a good piece of science".

In 1995, the notable paleoanthropologist Philip Tobias had declared that the savannah hypothesis was dead, because the open conditions did not exist when humanity's precursors stood upright and that therefore the conclusions of the Valkenberg conference were no longer valid. Tobias praised Morgan's book Scars of Evolution as a "remarkable book" though he said that he did not agree with all of it. Bender and Tobias further criticised the idea by pointing out that the coming out of the forest of man's precursors had been an unexamined assumption of evolution since the days of Lamarck, and followed by Darwin, Wallace and Haeckel, well before Dart used it.

Reactions of Hardy and Morgan

Alister Hardy was astonished and mortified in 1960 when the national Sunday papers carried banner headlines "Oxford professor says man a sea ape", causing problems with his Oxford colleagues. As he later said to his ex-pupil Desmond Morris, "Of course I then had to write an article to refute this saying no this is just a guess, a rough hypothesis, this isn't a proven fact. And of course we're not related to dolphins."

Elaine Morgan's 1972 book Descent of Woman became an international best-seller, a Book of the Month selection in the United States and was translated into ten languages. Part of this was related to the growing women's liberation movement as Morgan's work was inspired by a feminist critique of then-standard anthropological ideas. She assumed that the total lack of response to her book from the academic community was due to the fact that she was an outsider. "The response I had not foreseen was total silence. But in respect of the aquatic theme that is what I got from them - and with few exceptions still get. That kind of silence is a virtually unbeatable strategy". Morgan removed the polemics and rewrote the scientific part publishing it as The Aquatic Ape ten years later with the same response from academia.

Related academic and independent research

This section may lend undue weight to certain ideas, incidents, or controversies. Please help to create a more balanced presentation. Discuss and resolve this issue before removing this message. (March 2017)

Wading and bipedalism

After reviewing 30 different explanations of bipedalism, evolutionary biologist Carsten Niemitz proposed a "shore dweller" hypothesis of wading, though distancing himself from the AAH. He records 10 monkey and ape species, including chimpanzees and gorillas, who have been observed wading on two feet. Niemitz's hypothesis places the wading bipedalism of hominids as occurring in the Miocene, though evidence for seafood consumption by humans is, at oldest, from 200,000 years ago.

Researchers, including AAH proponent Algis Kuliukas, performed experiments to measure the comparative energy used when lacking orthograde posture with using fully upright posture. Although it is harder to walk upright with bent knees on land, this difference disappears in 30 centimeters of water and is still practical in thigh-high water.

Nutrients and brain size

Neanderthal skull (right) compared with modern human

In their 1989 book The Driving Force: Food, Evolution and The Future, biologists and proponents of AAH Michael Crawford and David Marsh explored the contribution of nutrition to human evolution, and in particular claimed that Omega-3 fatty acids were vital for the development of the brain. "A branch of the line of primitive ancestral apes was forced by competition to leave the trees and feed on the seashore. Searching for oysters, mussels, crabs, crayfish and so on they would have spent much of their time in the water and an upright position would have come naturally." Crawford and Marsh argue that the norm of brain size seen in small and aquatic mammals is similar to humans and they further opine that other primates and carnivores had lost relative brain capacity (though the relationship between brain size and intelligence is not isomorphic). Reviewing their book for the New Scientist, biologists Caroline Pond and Dick Colby were highly critical, saying that the work provided "no significant new information that would be of interest to biologists" and that its style was "speculative, theoretical and in many places so imprecise as to be misleading."

According to Michael Crawford, "the evolution of a large brain on the savannahs of Africa was impossible. The only way it could have happened was with the resources of the marine food-web which initiated the growth and development of the brain in the first place". A group of evolutionary nutritionists and paleontologists led by AAH proponents Stephen Cunnane, Kathlyn Stewart, and Michael Crawford published works arguing a correlation between aquatic diet and human brain evolution in their "shore-based diet scenario" while acknowledging Hardy/Morgan's thesis as a foundation work of their model. They describe problems in landlocked communities as being supportive of AAH, with reports of cretinism in the Alps since the 18th century and widespread goitres in parts of Africa, which is only prevented by the addition of iodine to diets. According to Cunnane, "Without the availability of iodized table salt, non-coastal (inland) habitats do not provide foods rich enough to meet human iodine requirements." Evidence supports aquatic food consumption in Homo as early as the Pliocene but its linkage to brain evolution remains controversial.

Stewart argues that Clarias catfishes provided an early source of dry season nutrition in the African rift valley.

What has been lacking has been the paleontological evidence that early humans consumed fish in significant amounts earlier than tens to hundreds of thousands of years ago. Part of the problem has been the avoidance of taphonomic bias by researchers: most hominin fossils occur in marginal lacustrine environments and the presence of fish remains is therefore no proof of fish consumption. Fish bones often decompose so that special tests are required to detect them. Also the archaeological record of human fishing and coastal settlement is fundamentally flawed due to postglacial sea level rise.

Diving behavior and performance

Physiologist Erika Schagatay, a proponent of AAH, in reviewing human diving abilities, suggested that they were consistent with seletive pressure for underwater foraging during human evolution, and discussed other anatomical traits speculated as diving adaptations by Hardy/Morgan, while biologist John Langdon suggested that such traits could be enabled by a human developmental plasticity.

File:Ear-with-exostoses.png
Inside of ear, with exostoses protecting the ear drum

Auditory exostosis

A narrowing of the ear canal due to bony growths protruding into the ear is caused by regular exposure to cold water. It is sometimes known as surfer's ear. Auditory exostoses have been seen in fossils of Homo erectus and Neanderthals, which demonstrates frequent swimming, according to the ENT specialist Peter Rhys-Evans. The idea that there is a genetic component has been discredited. A book by G. P. Rightmire reported exotoses in the skulls of Homo erectus, including one from the Lake Ndutu in the Olduvia Gorge. Evidence also has been found in Brazil dating back 5,000 years. This provides evidence that extensive swimming has been a characteristic of many human communities for longer than had been imagined.

See also

References

  1. ^ Attenborough 2016.
  2. Roede 1991. sfn error: no target: CITEREFRoede1991 (help)
  3. ^ Langdon 1997.
  4. Attenborough 2016, 18:54 Increase in aquatic research.
  5. ^ Cunnane & Stewart 2010.
  6. Stewart, K; Cunnane, S; Tattersall, I, eds. (2014). "Special Issue: The Role of Freshwater and Marine Resources in the Evolution of the Human Diet, Brain and Behavior". Journal of Human Evolution. 77: 1–216. {{cite journal}}: Invalid |ref=harv (help)
  7. "The Matrix of Comparative Anthropogeny (MOCA) -- Aquatic Food Consumption". Center for Academic Research & Training in Anthropogeny. {{cite web}}: Invalid |ref=harv (help)
  8. Bender R, Tobias PV, Bender N (2012). "The Savannah hypotheses: origin, reception and impact on paleoanthropology". Hist Philos Life Sci (Historical article). 34 (1–2): 147–84. PMID 23272598.
  9. Westenhöfer 1942, p. 148.
  10. Westenhöfer, Max (1942). Der Eigenweg des Menschen. Dargestellt auf Grund von vergleichend morphologischen Untersuchungen über die Artbildung und Menschwerdung. Berlin: Verlag der Medizinischen Welt, W. Mannstaedt & Co. pp. 309–312. Retrieved 6 November 2016. {{cite book}}: Invalid |ref=harv (help)
  11. Westenhöfer Max (1948) Die Grundlagen meiner Theorie vom Eigenweg des Menschen: Entwicklung, Menschwerdung, Weltanschauung. Carl Winter Heidelberg. ISBN 978-3533019695.
  12. Reeve, Eric. Book review: "The Aquatic Ape: Fact or Fiction?" (PDF). Genetical Research (Cambridge University Press), Volume 59 Issue 01 (February 1992): p. 64.
  13. ^ Hardy 1960.
  14. Sauer, Carl O. (1960). "Seashore–Primitive home of man?". Proceedings of the American Philosopical Society. 106 (1): 41–7. JSTOR 985209. {{cite journal}}: Invalid |ref=harv (help)
  15. Erlandson, J. M. (2001). "The archaeology of aquatic adaptations: paradigms for a new millennium". Journal of Archaeological Research. 9 (4): 287–350. {{cite journal}}: Invalid |ref=harv (help)
  16. Morris, Desmond (1967). The Naked Ape. McGraw-Hill. p. 29. ISBN 0-09-948201-0.
  17. Morgan, Lewis H (1877). Ancient Society. New York: Henry Holt & Co. p. 10. Retrieved 29 October 2016.
  18. Dart, Raymond A. (1953). "The Predatory Transition from Ape to Man". International Anthropological and Linguistic Review. v. 1 (4). Retrieved 29 October 2016.
  19. Morgan 1972, p. 11.
  20. Hardy, Alister Clavering (1977). "Was there a Homo aquaticus?". Zenith. 15 (1): 4–6.
  21. Morgan 1990, pp. 69–79.
  22. Langdon (1997), p. 483
  23. Wood Jones, Frederic (1929). Man's Place among the Mammals. Longmans, Green & co. p. 309. Retrieved 4 February 2017.
  24. Langdon (1997), p. 481
  25. Hardy 1960, p. 645.
  26. Langdon (1997), p. 487
  27. Kuliukas, Algis V.; Morgan, Elaine (2011). "Aquatic Scenarios in the Thinking on Human Evolution: What are they and How do they Compare?": 106–119. Retrieved 4 February 2017. {{cite journal}}: Cite journal requires |journal= (help)
  28. Reynolds, Vernon (1991). Cold and Watery? Hot and Dusty? Our Ancestral Environment and Our Ancestors Themselves: an Overview. p. 340. in Roede 1991 harvnb error: no target: CITEREFRoede1991 (help)
  29. Dunsworth, H.M. (2007). Human Origins 101. ABC-CLIO. p. 121. ISBN 978-0-313-33673-7.
  30. McNeill, D (2000). The Face: A Natural History. Back Bay. pp. 36–37. ISBN 0-316-58812-1. {{cite book}}: Invalid |ref=harv (help)
  31. Trauth, M. H.; Maslin, M. A.; Deino, A. L.; Junginger, A.; Lesoloyia, M.; Odada, E. O.; Olago, D. O.; Olaka, L. A.; Strecker, M. R.; Tiedemann, R. (2010). "Human evolution in a variable environment: The amplifier lakes of Eastern Africa" (pdf). Quaternary Science Reviews. 29 (23–24): 2981–2988. Bibcode:2010QSRv...29.2981T. doi:10.1016/j.quascirev.2010.07.007. {{cite journal}}: Invalid |ref=harv (help)
  32. Graham, J.M.; Scadding, G.K.; Bull, P.D. (2008). Pediatric ENT. Springer. p. 27. ISBN 3-540-69930-9. {{cite book}}: Invalid |ref=harv (help)
  33. Hawks JD (4 August 2009). "Why anthropologists don't accept the Aquatic Ape Theory" (Blog post).
  34. Frazier K (2015). "Quacks and cranks, GMOs and climate, science and philosoph—CFI Conference covers it all". Skeptical Inquirer. 39 (5): 12. Retrieved 25 February 2017.
  35. Gee, Henry (2013). The Accidental Species: Misunderstandings of Human Evolution. U of Chicago Press. p. 115. Retrieved 6 January 2017. {{cite book}}: Invalid |ref=harv (help)
  36. Foley, Robert; Lahr, Marta Mirazón (2014). "The Role of "the Aquatic" in Human Evolution: Constraining the Aquatic Ape Hypothesis". Evolutionary Anthropology. 23: 56–59.
  37. Dennett, Daniel (1995). Darwin's Dangerous Idea. Penguin. p. 244. Retrieved 4 February 2017.
  38. Milam, Erika (2013). "Dunking the Tarzanists. Elaine Morgan and the Aquatic Ape theory". Outsider Scientists. Routes to Innovation in Biology. Univ of Chicago Press. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help); Unknown parameter |editors= ignored (|editor= suggested) (help)
  39. Charlton, Bruce (5 January 1991). "How the apes lost their fur". British Medical Journal. 302: 58. doi:10.1136/bmj.302.6767.58.
  40. Tobias, Philip. Foreword: Evolution, Encephalization, Environment. p. viii. in Cunnane & Stewart 2010, pp. vii–xii
  41. Tobias, Philip V (1998). "Water and Human Evolution". Dispatches Human Evolution. Retrieved 16 January 2017. {{cite journal}}: Invalid |ref=harv (help)
  42. Bender, Renato; Tobias, Phillip V.; Bender, Nicole (2012). "The Savannah Hypotheses: Origin, Reception and Impact on Paleoanthropology". Hist. Phil. Life Sci. 34: 147–184.
  43. Morgan 2008, p. 12.
  44. Morgan 2008, p. 15.
  45. Morgan 2008, p. 17.
  46. ^ Niemitz, Carsten (2010). "The evolution of the upright posture and gait—a review and a new synthesis". Naturwissenschaften. 97: 241–263. doi:10.1007/s00114-009-0637-3. Retrieved 4 February 2017. {{cite journal}}: Invalid |ref=harv (help)
  47. Niemitz C (2002). "A Theory on the Evolution of the Habitual Orthograde Human Bipedalism – The "Amphibische Generalistentheorie"". Anthropologischer Anzeiger. 60: 3–66.
  48. Niemitz, Carsten (2004). Das Geheimnis des Aufrechten Gangs ~ Unsere Evolution Verlief Anders. Beck. ISBN 3-406-51606-8.
  49. Niemitz 2010, pp. 254, 5.
  50. Gee, Henry (7 May 2013). "Aquatic apes are the stuff of creationism, not evolution". The Guardian. ISSN 0261-3077. Retrieved 16 March 2017.
  51. Kuliukas, Algis V; Milne, Nick; Fournier, Paul (2009). "The relative cost of bent-hip bent-knee walking is reduced in water". Journal of Comparative Human Biology. 60: 479–488. doi:10.1016/j.jchb.2009.09.002. {{cite journal}}: |access-date= requires |url= (help)
  52. Halsey, Lewis G; Tyler, Christopher J; Kuliukas, Algis V (2014). "The energy costs of wading in water". Biology Open. 3 (7). doi:10.1242/bio.20147831. {{cite journal}}: |access-date= requires |url= (help)
  53. Crawford & Marsh 1989.
  54. Crawford & Marsh 1989, p. 162.
  55. Crawford & Marsh 1989, p. 159.
  56. Pond C, Colby D (27 January 1990). "The Driving Force: Food, Evolution and The Future by Michael Crawford and David Marsh". New Scientist (Book review).
  57. Stewart, Cunnane & Tattersall 2014.
  58. Cunnane, SC (2005). Survival of the fattest: the key to human brain evolution. World Scientific. {{cite book}}: Invalid |ref=harv (help)
  59. Stewart, Kathlyn M.; Cunnane, Stephen C. (2010). "Introduction": xiii–xvii. {{cite journal}}: Cite journal requires |journal= (help); Invalid |ref=harv (help) in Cunnane & Stewart 2010
  60. Broadhurst et al. 2002, pp. 659–660. sfn error: no target: CITEREFBroadhurstWangCrawfordCunnane2002 (help)
  61. Venturi, Sebastiano and Michel E. Bégin (2010). "Thyroid Hormone, Iodine and Human Brain Development": 112. {{cite journal}}: Cite journal requires |journal= (help) in Cunnane & Stewart 2010, pp. 105–124
  62. Cunnane 2010, p. 47. sfn error: no target: CITEREFCunnane2010 (help)
  63. Braun, David R.; Harris, John W. K.; Levin, Naomi E.; McCoyb, Jack T.; et al. (2010). "Early hominin diet included diverse terrestrial and aquatic animals 1.95 Ma in East Turkana, Kenya". Proceedings of the National Academy of Sciences. 107 (22): 10002–7. doi:10.1073/pnas.1002181107. {{cite journal}}: |access-date= requires |url= (help); Explicit use of et al. in: |first4= (help)
  64. Carlson, B. A.; Kingston, J. D. (2007). "Docosahexaenoic acid, the aquatic diet, and hominin encephalization: difficulties in establishing evolutionary links". American Journal of Human Biology. 19 (1): 132–141. {{cite journal}}: Invalid |ref=harv (help)
  65. Cunnane, S. C.; Plourde, M.; Stewart, K.; Crawford, M. A. (2007). "Docosahexaenoic acid and shore‐based diets in hominin encephalization: A rebuttal". American Journal of Human Biology. 19 (4): 578–581. {{cite journal}}: Invalid |ref=harv (help)
  66. ^ Stewart 2010. sfn error: no target: CITEREFStewart2010 (help)
  67. Stringer & Andrews 2005. sfn error: no target: CITEREFStringerAndrews2005 (help)
  68. Erlandson, Jon M. "Food for Thought: the Role of Coastlines and Aquatic Resources in Human Evolution". {{cite journal}}: Cite journal requires |journal= (help) in Cunnane & Stewart 2010, pp. 125–136
  69. Schagatay, E. (2011). "Human Breath-Hold Diving Ability Suggests a Selective Pressure for Diving During Human Evolution": 120–147. {{cite journal}}: Cite journal requires |journal= (help) in Vaneechoutte, Kuliukas & Verhaegen 2011
  70. Langdon, J. (2012). "Book review of 'Was Man More Aquatic in the Past? Fifty Years after Alister Hardy: Waterside Hypotheses of Human Evolution', Mario Vaneechoutte, Algis Kuliukas, Marc Verhaegen (Eds.)". HOMO - Journal of Comparative Human Biology. 63: 315–318.
  71. Rhys Evans, Peter H. (1992). "The parasunal sinuses and other enigmas: an aquatic evolutionary theory". Journal of Laryngology and Otology. 106: 214–225. {{cite journal}}: Invalid |ref=harv (help)
  72. Wong, Brian J.; Cervantes, William; Doyle, Karen Jo; et al. (1999). "Prevalence of External Auditory Canal Exostoses in Surfers". 125 (9). Arch Otolaryngol Head Neck Surg.: 969–72. PMID 10488981. {{cite journal}}: Cite journal requires |journal= (help); Explicit use of et al. in: |first3= (help)
  73. Rhys-Evans, P. H.; Cameron, M. (2014). "Surfer's Ear (Aural Exostoses) Provides Hard Evidence of Man's Aquatic Past". Human Evolution. 29 (1/3): 75–90.
  74. Rightmire, G. Philip (1990). The Evolution of Homo Erectus: Comparative Anatomical Studies of An Extinct Human Species. Cambridge University Press. p. 51. ISBN 0521308801.
  75. Okumura, Maria Mercedes M.; Boyadjian, Célia H.C.; Eggers, Sabine (2007). "Auditory Exostoses as an Aquatic Activity Marker: A Comparison of Coastal and Inland Skeletal Remains From Tropical and Subtropical Regions of Brazil". American Journal of Physical Anthropology. 132: 558–567.

Bibliography

Aquatic ecosystems
General components and freshwater ecosystems
General
Freshwater
Ecoregions
Marine ecosystems
General
Marine life
Microorganisms
Vertebrates
Marine habitats
Conservation
Human evolution
Taxonomy
(Hominins)
Last common ancestors
Australopithecines
Ardipithecus
Australopithecus
Paranthropus
Humans and
proto-humans
(Homo)
Proto-humans
Homo erectus
Archaic humans
Modern humans
Homo sapiens
Ancestors
Models
General models
Specific models
Topics
Origin of modern humans
Timelines
Others
Human genetics
Sub-topics
Genetic history
by region
Population genetics
by group
Apes
Extant
ape species
Study of apes
Legal and
social status
Related
Portals: Categories: