DOC - Semi aquatic ancestor

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Neoteny and paedomorphosis
The hypothesis I present about aquatic reflexes of newborn H. sapiens has no sense if not connected with the two
concepts neoteny and paedomorphosis. In combination neoteny and paedomorphosis are more than an age in
discussion for several properties of H. sapiens. In developmental biology paedomorphosis in a species are
phylogenetic characters revealed in adults that retain traits previously seen only in juveniles. As example humans are
actually thought to be paedomorphic due to a flattened face and receded lower yaw compared to other adult primates.
Fig. 8 Facial neoteny original examples
This is presented in 1948 in Westenhofer10 (fig. 8a) and still repeated (with 8b) many times with the chimps’ baby’s
stadium forming an adult human face. The photographs are from A. Naef6.
The comparison is repeated recently in anthropology by Penin et al. 8
Two explanations are mentioned; the extension of brains of hominin ancestors to our genus Homo (fig M. 1mln 
now) and domestication leading to a lesser jaw and smaller set of teeth.
Fig. Meijers
The process of evolution by which the increase in the length of human developmental periods has been accomplished
is mentioned as neoteny. Neoteny describes effects of a process by which paedomorphism is achieved. Ultimately it
results in retention of juvenile physical characteristics in adults of a species well into maturity. Man’s large head, flat
face, round headedness, small face and teeth, absence of brow ridges, thinness of skull bones, late suture closure,
relative hairlessness, thin nails, prolonged period of educability, playfulness, love of fun, and many other traits all
constitute evidence of neoteny.
Neotenic and paedomorphic popular states in humans are characteristics in women and widely acknowledged as
desirable by men (sexual attraction, Jones3 andMorris5). Morris discussed this in the importance of neoteny in human
sociobiology and with fig. 8 I give an example: “female” facial properties are bigger eyes with more white visible,
more cheek and a smaller, shorter chin, lips bigger and more red visible, hairless face and more “fully hair style”. In
higher developed cultures this is accentuated with makeup, lipstick , hair styling and more. Observed is that
competitive females look at other females (concurrence) and it influences role models.
In our "human ape" status it is a fact that alpha males are keen on "scoring" more (young) females and in that way
biologically produce more offspring than lesser dominant males. I take it for granted that you are familiar with that
phenomenon. Ethological point here is that we can state that the alpha males do this
unaware of the progenetical outcomes.
Famous example scientifically accepted is Genghis Khan (c. 1162-1227), a world renowned 13th century Mongol
Emperor.
Due to the expansive and prolonged rule of Khan, sons and grandsons in Asia and Europe in the Mongol Empire,
modern day DNA studies
have indicated that a specific Y-chromosomal lineage with patterns suggest that it originated from Mongolia about
1000 years ago.
This marker can now be found in 8% of men in a large region of Asia and parts of Europe.
His descendants extended the empire and maintained power in the region for several hundred years, in civilizations
in which harems and
concubines were the norm. And the males were markedly prolific (The Genetic Legacy of the Mongols).
Fig. 8 Neoteny in humans
Hairless and baby-like body skin in general shows the same. There are differences between different dispersed
Human populations, but “attractive” is general and also cultural tailored by depilating and shaving. An enormous
profitable industry is thriving on it.
Then there is the “childlike” higher pitch of female voicing that plays an important role in different social aspects. It
is connected to attractiveness, protection against aggressiveness and realizing care. A lot of literature is available
about striking values (Feinberg et al.1) of pitch difference between males and females, and the – instinctive- use in
context of many social interactions.
Al mentioned about female aspects can repeated for man in the other way. Hairy, lower voice: the lower the better,
less wide eyes, bigger chin….
Socio-biology and ethology are producing an endless list of descriptions about the interactions in H. sapiens contacts
and communities.
A point to mention at last is the result of research to transcriptional neoteny in H .sapiens. Not as visible as the
examples mentioned, but it is important it shows that neoteny in H. sapiens is acting considerably on separate levels
(Somel et al.9).
There is more to look into, but not all known and supposed human neotenic properties are important to the aquatic
traits of our newborns I focus to. The aspect of human newborns in water in fact reminds anyway about original
neotenic developmental properties as described by Lorenz 4 , Morris5 and Gould2 of different animals, humans as
well. Lorenz description of neoteny is an example(cursive: Lorenz, p.133):
“The apparent exception to Dollo’slaw* thus occurs only where neoteny affects forms whose juvenile stages are rich
in ancestral characters. In other words, it only involves “palingenetic**characters that are recapitulated from
ancestral forms. It was necessary to discuss all of this in some detail because human beings correspond to the
juvenile stages of anthropoid apes in a large number of features, both in morphology and in the realm of innate
behaviour. Because a number of these persistent juvenile features of humans are ancestral characters, authors that
failed to take into account the principles of neoteny set out above have repeatedly cited them as arguments against
our derivation from anthropoid apes. In reality, they do not provide such negative evidence.”
He did not point to aquatic activities of newborns but his statement is significant. Neotenic in combination with
paedomorphic retention of (foetal and) juvenile characters into adult life is defined as link to possible original
ancestral properties. They can be connected to possible ancestral anthropoid (pre-human) apes. Important is that
newborns AND adults correspond in some properties of morphology and physiology and innate behaviour
components are mentioned.
Newborn properties are frequently exempted and in my view the declaration I propose is ‘free’. The important
point is not the value of the examples I described. Neoteny and paedomorphosis aspects in H .sapiens are not only
the socially important ones. Many are involved in physiological and morphological properties of adults.
Aquatic adaptation of H. sapiens is involved, a paedomorph form of our neonate properties. And if aquatic adaptive
behaviour in our species is comparable to Lorenz’ definition of neoteny, than it is allowed to connect that with
ancestral characters.
Fig. 9. Myanmar: Sea-gypsy children playing. http://www.allmyanmar.com/index.html
I did mention that if my proposed hypothesis is accepted, it has no sense if the concepts neoteny and paedomorph are
not connected. Accepting it means that early human ancestors could indeed have undergone forced adaptation in
restricted sets of habitats leading to aquatic morphological and behavioural properties. About when and where
exactly and with “whom” leaves speculating.
It is important to establish not only aquatic reflexes in newborn humans. If we take the evidence ethological in
consideration it presents a hint to ancestral H. sapiens behaviour in and preference for aquatic and semi-aquatic
habitats for children, adolescents and adults (Niemitz7).
I propose that juvenile aquatic properties of human newborn babies and toddlers can be neotenic and paedomorphic
examples of aquatic adapted mature H. sapiens. Newborns and little children are very quick aquatically adapted. The
physiological properties do encompass diving, controlling breath, early swimming movements and floating. All H.
sapiens starting as newborns or very little children to swim and dive, they continue it from adolescence to maturity.
The process to develop this has as I describe a striking ethological aspect.
Swimming, diving, playing in and near water is indeed an important natural behaviour for all human stages Niemitz 7
described. To this fits that hands free together with bipedalism can be connected to aquatic adaptations as he also
mentioned. Bipedal abilities came first and after this gradually the ‘extras’ of tool use and skilful dispersion with
more brains in bigger skullcap. And then we have course mention long distance swimming, (very) deep diving and
floating on almost everything available. Not only for playing but also to able foraging, dispersing, transporting and
traveling. There are changing views that carefully can open those possible probabilities, like mentioned in
Wrangham11 et al..
Ama pearl diving women © Japanese Element Symbols Web Portal
Given that early hominines in the tropics lived in relatively dry habitats, while others occupied temperate latitudes,
ripe, fleshy fruits of the type preferred by African apes would not normally have been available year round. We
therefore suggest that water-associated USOs* were likely to have been key fallback foods, and that dry season
access to aquatic habitats would have been an important predictor of hominin home range quality. This study differs
from traditional savannah chimpanzee models of hominin origins by proposing that access to aquatic habitats was a
necessary condition for adaptation to savannah habitats. It also raises the possibility that harvesting efficiency in
shallow water promoted adaptations for habitual bipedalism in early hominines.
(*USO’s: aquatic or semi aquatic underground storage organs of plants (Meijers)).
Could a next explorative activity be facilitated by ancestral aquatic adaptations as we see it in newborn H. sapiens
and in the other mentioned properties? Maybe we even need to point to a strong possible option to declare the speed
of world wide human dispersal along shores, riverbanks and over water to many remote islands and archipelagos.
Additions
1. *Dollo’s law (1857-1931) is a hypothesis proposed in 1890 that states that evolution is not reversible, suggesting
“irreversibility” of certain evolutionary pathways. Lorenz mentions already “apparent exception”. What is known
now about complex DNA organization learns that he was in some sense right. Some of your vertebrate ‘home-box’
genes are much the same as in Drosophila, so who knows.... (Meijers).
** Palingenetic definition in biology:
a. Embryonic development that reproduces ancestral features of species.
b. Obsolete: the supposed generation of organisms from others preformed in the germ cells.
2. Iwant to mention at last three properties that are neotenic and visible paedomorphic fitting in the line I depicted:
Lack of fur preventing cooling in semi aquatic habitats (try a wet t-shirt contest yourself)
Active water repellent sebum production of newborns (and more of foetuses) on skin maintained in all stages up to
pubertal and adult humans
Subcutaneous fat, a useful isolating aquatic adaptation for babies and adolescent humans.
References
Feinberg D.R. Jones B.C. De Bruine L.M. Moore F.R. Law Smith M.J. Cornwell R.E. Tiddeman B.P.Boothroyd
L.G. Perrett D.I. 2005. The voice and face of woman: One ornament that signals quality? Evolution and
Human Behavior 26 (2005) 398–408
Gould SJ 1977. Ontogeny and phylogeny. President and Fellows of Harvard College USA
Jones D. 1995. sexual selection physical attractiveness and facial neoteny. Cross-cultural evidence and
implications. Current anthropology 36 - 5
Lorenz K. 1997. The natural science of the human species. (The Russian Manuscript 1944-1948). MIT press
Massachusetts USA
Morris D. 1967. The naked ape.Jonathan Cape, London UK
Naef a. 1926. Über die Urformender Anthropomorphen und die Stammengeschichte des Mensenschädels, Die
Naturwissenschaften 14 pp. 445-452.
Niemitz C. 1991. Das geheimniss des aufrechten ganges. C. H. Beck Verlag, München BRD
Penin X. Berge C. Baylac M. 2002. Ontogenetic study of the skull in modern humans and the common
chimpanzees: neotenic hypothesis reconsidered with a tridimensional Procrustes analysis. American
Journal of Physical Anthropology vol 118, no 1, p 50-62.
Somel M. Franz H. Yan Z. Lorenc A. Guo S. Giger T. Kelso J. Nickel B.
Dannemann M. Bahn S. Maree J.Webster M.J. Weickert C.S. Lachmann M. Transcriptional neoteny in
the human brain. PNAS April 7, 2009 vol. 106 no. 14
Westenhöfer M. 1948. Eigen wegdes Menschen, die Gründlagen meiner
Theorie vom…Carl Winter Universitätsverlag Heidelberg.
Wrangham R. Cheney D. Seyfarth R.Armiento E. 2009. Shallow-water habitats as sources offallback foods for
hominins. American Journal of Physical Anthropology 140:630–64
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