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Was Man more aquatic in the past?
Mario VaneechoutteMarc Verhaegen
May 27th 2011ECCOVUB
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Homo sapiens is a very special species
Walking fully upright: fully bipedal
Large brain (3 times larger than chimp and gorilla)
Speech Reflexive awareness (Consciousness) 1
Thinking about the future Religiosity 2
Science, technology
1. Vaneechoutte, M. 2000. Experience, awareness and consciousness: suggestions for definitions as offered by an evolutionary approach. Foundations of Science 5: 429-456.
2. Vaneechoutte, M. 1993. The memetic basis for religion. (Correspondence Letter). Nature 365: 290.
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Homo sapiens is an extremely special primate/animal1. Only fully upright animal (except pinguins?)2. Hairless: naked3. Streamlined4. Subcutaneous fat/ Extremely fat (and helpless?) neonates5. Our bodies are wasteful with water and salt
Sweat glands all over the bodyMultipyramidal reins
6. External nose - everted lips - philtrum/Mouth breathing7. Voluntary breath control/Diving reflex8. Reduced colour vision9. Reduced olfactory capacity (smell)10. Increased manual dexterity and tactility11. Sexuality: Face-to-face mating - Hymen - Menstrual cycle12. Large brains13. Sea food, Song and Speech
The Aquatic Ape Hypothesis (AAH) claims that all of these characteristics are most straightforwardly explainedby assuming that they evolved as adaptations to a swimming/diving lifestyle of our direct hominin ancestors.
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Introduction: Reactions to the notion that our ancestors may have been more aquatic
Reaction 1. "Of course. I knew that already: All animals originated from the water."
But: the AAH is not about the transition from fish to amphibian, which took place 400 million years ago (mya), but about the transition from ape to human, from 7 mya onwards.
Fish : fully aquatic (exc. e.g. lung fish) Amphibians: amphibious = semi-aquatic: 400 mya (Devonian) Reptiles: ancestor is fully terrestrial: 320 mya (Carboniferous) Birds: ancestor is fully terrestrial 150 mya (late Jura) Mammals: ancestor is fully terrestrial 220 mya (Trias)
Hominoids: ancestor is (aqu?)arboreal 27 mya (Oligocene)Latest ancestor gorilla - chimp - humans: 7-5 myaSemi-aquatic phase of direct human ancestors: 7-5 mya: Morgan
< 7- 50.000 years ago: Verhaegen
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Introduction: Reactions to the notion that our ancestors may have been more aquaticReaction 2: "Going back to the water: what a crazy idea!"
In fact, transitions between different habitats happen all of the time during evolution.
When not specialized too strongly, animal groups may switch water, land, tree, air habitats, when environmental conditions are changing
Reptilesland to water: Ichtyosaurus (†), Mosasaurus (†), water turtles, crocodiles, water snakesland to air: Pterosaurus (†), Archaeopteryx (†): birds
Birdsair to land: ostriches, kiwi, dodo (†) air to land-water: pinguins
Mammalsland to air: batsland to land-water: seals, sea lions, walruses, hippopotamus, ancestors (†) of elephants & pigsland to water: dolphins, whales, sirens (dugongs and manatees: sea cows))land-water to land: elephants, pigs, hippopotamus
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Fully aquatic: all food from the water)Platypus (duck bill), water possummusk rat, otter, babirusa, ice bear, fish cat, water civet cat,
Mammals frequently feeding in/at water (can dive at least one minute): beaver, elephant, tapir, hippo, babirusa, eland, wash bear, marsh rabbit
Primates frequently feeding in/at water (can dive at least one minute):Rock macaque/ Japanese macaque, long-nosed ape, humans
Introduction: Reactions to the notion that our ancestors may have been more aquaticReaction 2: "Going back to the water: what a crazy idea!"
Below is a non-exhaustive list of water-adapted mammals:
Humans: monkeys: trees apes trees-water (aquarboreal): 20 mya
ancestor Homo: water-land (amphibious diver): 7 mya H. sapiens land: 50 000 ya
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Introduction: Reactions to the notion that our ancestors may have been more aquatic
Reaction 3: "What an odd proposition!: The AAH states that we were were first terrestrial apes, thereafter went to the sea and turned into dolphins, and then came back on land to look like chimps again."
In fact,That we were once fully aquatic is not a claim of the Aquatic Ape Hypothesisbecause Hardy asked only: "Was Man more aquatic?"
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Introduction: Reactions to the notion that our ancestors may have been more aquatic
Reaction 4: "Quite unlikely! Apes, and many humans are afraid of water and are poor swimmers."
Elaine Morgan: 'Hotel rooms with a sea-view are the most expensive ...'and our fondness of water may be noticed from the illustration below.
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Japanese macaques bathing in hot spring Swimming proboscis monkey
Introduction: Reactions to the notion that our ancestors may have been more aquatic
Reaction 4: "Quite unlikely! Apes, and many humans are afraid of water and are poor swimmers."
Some examples of swimming/bathing monkeys
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Wading lowland gorilla
Introduction: Reactions to the notion that our ancestors may have been more aquatic
Reaction 4: "Quite unlikely! Apes, and many humans are afraid of water and are poor swimmers."
Wading bonobo with stick
Some examples of wading apes (hominids)
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Introduction: Reactions to the notion that our ancestors may have been more aquaticReaction 4: "Quite unlikely! Apes, and many humans are afraid of water and are poor swimmers.We have to learn to swim."
But Hardy remarked:
Hardy A. 1960. Was Man more aquatic in the past? New Scientist 7: 642-645.
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Hardy A. 1960. Was Man more aquatic in the past? New Scientist 7: 642-645.
Reaction 4: "Quite unlikely! Apes, and many humans are afraid of water and are poor swimmers.We have to learn to swim...."
For the sake of animal wellfare:Don't try this with chimp babies!
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Discipline Aim Method Male record Female record
Static apnea (STA) duration apnea at rest floating in a pool 11’ 35” 8‘ 23’’
Dynamic apnea with fins (DYN)
distance horizontal swimming in a pool with fins 265 m 225 m
Dynamic apnea without fins (DNF
distance horizontal swimming in a pool without fins 218 m 160 m
Constant weight with fins (CWT)
depth vertical swimming down and up with fins 124 m 101 m
Constant weight without fins (CNF)
depth vertical swimming down and up without fins 95 m 62 m
Free immersion (FIM)
depth pulling down and up on a rope 120 m 85 m
In fact: we are excellent divers and swimmers and can support apnea during long periodsCurrent world records
Schagatay E. 2011. Chapter 7. WMMA?
Reaction 4: "Quite unlikely! Apes, and many humans are afraid of water and we are poor swimmers."
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Introduction: Reactions to the notion that our ancestors may have been more aquaticReaction 5: "No way! Everyone knows that our ancestors were savannah hunters."
In fact, the savannah hypothesis has been long abandoned (only: few people seem to realize that!?)Quotes from Morgan. 1997. The aquatic ape hypothesis. p. 17:
Leakey R, Lewontin R. 1992. Origins reconsidered, p. 85. Little Brown, London."In fact, the immense plains and the immense herds on themare relatively recent aspects of the African environment, much more recent than the origin of the human family."
Wood B. 1996. Nature 379: 687"The savannah 'hypothesis' of human origins, in which the cooling climate begat the savannah and the savannah begat humanity, is now discredited."
Hunt KD. 1994. J Human Evol 26: 191."Recent evidence suggests that the common supposition that australopithecineswere grassland adapted is incorrect."
Tobias PV. 1995. Daryll Forde Memorial Lecture. Univ College London."All the former savannah supporters (including myself) must now swallow our earlierwords in the light of the new results from the early hominid deposits.Of course, if savannah is eliminated as a primary cause, or selective advantage of bipedalism, then we are back to square one and have to try to find consensus on some other primary cause."
Introduction: Reactions to the notion that our ancestors may have been more aquatic
Reaction 6: "Going from trees to land, via water, is not parsimonious"
Law of parsimony (Occam's razor)is a principle that generally recommends selecting the competing hypothesis that makes the fewest new assumptions, when the hypotheses are equal in other respects
It is a useful principle to approach evolutioniary dynamics.But it is not a dogma!
Indeed, some monkeys went directly from tree to savannah: baboon, vervet monkey, marmoset monkey:they are quadrupedal, fully haired, large snouts, ...
Moreover: Were our ancestors purely arboreal? Or rather aquarboreal: tree + water
Moreover: Are we at present typically terrestrial? Cunnane S.: we are still very dependent on iodine and omega3 for normal brain development
Lack of iodine: cretinism. This is unexpected for a terrestrial species! 16
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In France, children born with cretinism were considered to be so mentally retarded that they were even incapable of committing sin.
Thus the name cretinism, meaning Christlike.
"Iodine deficiency: world's most serious nutritional deficiency, adversely affecting nearly a billion people"Cunnane CS. 2005. Survival of the fattestLoss of iodine from soils through erosionMost deficiency in mountain and inland regionsLeading to hypyothyroidism and cretinism
Are we a terrestrial species? Need for iodine for normal development ...
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Sources of iodine?Gram of food needed to meet daily iodine requirement
Introduction: Reactions to the notion that our ancestors may have been more aquaticReaction 6: Going from trees to land, via water, is not parsimonious
Moreover: Are we now typically terrestrial? Cunnane S.: we are still very dependent on iodine and omega3 for normal brain development
Lack of iodine: cretinism. This is unexpected for a terrestrial species!
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Sir Alister Hardy
Sir Alister Hardy. 1960. A marine biologist.
He based his ideas on those of Wood Jones (1929), who specifically focused on our skin:naked, thick and with subcutaneous fat.
after noticing the subcutaneous blubber of marine animals.He kept these ideas 30 years for himself ...:"I have been toying with this concept of Man's evolution for many years, but until this moment, which suddenly appeared to be an appropriate one, I had hesitated because it had seemed perhaps too fantastic; yet the more I reflected upon it, the more I came to believe it to be possible, or even likely."
Picked up by Desmond Morris in some of his documentaries
This inspired Elaine Morgan (1972), feminist journalist
Her books have inspired several othersWood Jones F. 1929. Man's place among the mammals. Edward Arnold, London.Hardy A. 1960. Was Man more aquatic in the past? New Scientist 7: 642-645.Morgan E. 1972. The descent of woman. Stein and Day, New York.
Introduction: Brief history of the idea
20Morgan E. 1972. The descent of woman. Stein and Day, New York.
21Morgan E. 1997. The aquatic ape hypothesis. Souvenir Press, London.
22Verhaegen, M. 1997. In den beginne was het water. Hadewijch, Antwerpen
Primates: galago, indri, maki, lemur
Monkeys
Hominoids
Monkeys: S. American primates, capucine, tamarin,
vervet monkey, marmosetbaboon, macaque
Apes (Hominoids):
Hominids:(great apes)
orangutan gorilla (Gorilla)
chimp (Pan)man (Homo)
Introduction: extant primates
Hylobatidae(lesser apes)
gibbonsiamang
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Homo sapiens is an extremely special primate/animal
1. Only fully upright animal (except pinguins?)2. Hairless: naked3. Streamlined4. Subcutaneous fat/ Extremely fat (and helpless?) neonates5. Our bodies are wasteful with water and salt
Sweat glands all over the bodyMultipyramidal reins
6. External nose - everted lips - philtrum/Mouth breathing7. Voluntary breath control/Diving reflex8. Reduced colour vision9. Reduced olfactory capacity (smell)10. Increased manual dexterity and tactility11. Sexuality: Face-to-face mating - Hymen - Menstrual cycle12. Large brains13. Sea food, Song and Speech
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Humans are extremely special primates/animals1. The only fully upright terrestrial bipedals
bipedals not fully upright: dinosaurs birds kangooroo, jumping mice
occasionally upright bipedal mammals: bears, bush antilopes, mangustoccasionally upright bipedal primates: gibbon, long-nosed monkey, gorilla, bonobo
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Humans are extremely special primates/animals1. Humans are the only fully upright terrestrial bipedals
Exception?: pinguin semi-aquatic well-adapted diver
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Humans are extremely special primates/animals1. The only fully upright terrestrial bipedalsException? One monkey walks frequently uprightThe proboscis monkey (Nasalis larvatus) or long-nosed monkeya reddish-brown aquarboreal monkey, endemic to Borneo.
http://en.wikipedia.org/wiki/File:Portrait_of_a_Proboscis_Monkey.jpg
The Proboscis monkey's lifestyle is both arboreal and amphibious, with its mangrove swamp and riverine environment containing
forestdry landshallow water allowing wadingdeep water requiring swimming.
Like other monkeys, the Proboscis monkey climbs well. Proficient swimmer, often swimming from island to island.Has been picked up by fishing boats in open ocean a mile from shore. While wading, the monkey uses an upright posture, with the females carrying infants on their hip. Troops have been filmed continuing to walk upright, in single fileThe only non-human mammal, with the exception of gibbons and giant pangolinsknown to use this form of locomotion on land for any length of time.
Most frequently upright walking hominid: bonobo. Lives in swampy forest
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Humans are extremely special primates/animals2. Hairless: naked
Very special skin, compared to terrestrial mammas and primates: hairs reducedapocrine glands: disappear before birtheccrine glands all over, instead of only at padssebaceous glands: numerous, very active
Morgan E. 1997. AAH
Land mammals, apes Humans
Eccrine glands
Sebaceous glands
Apocrine glands
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Humans are extremely special primates/animals2. Hairless: naked
30Morgan E. 1997. AAH
Humans are extremely special primates/animals3. Streamlined
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f
Humans are extremely special primates/animals3. StreamlinedMore streamlined than what?
32Morgan E. 1997. AAH
Humans are extremely special primates/animals3. StreamlinedThe hairs that we have left, grow in an orientation, unseen in other primatesHardy suggested that this might have evolved for reduced drag while swimming in water:"particularly to be noted are the hairs on the back, which are all pointing in lines to meet diagonally towards the mid-line, exactly as the streams of water would pass round the body and meet, when it is swimming forward like a frog. Such an arrangement of hair, offering less resistance, may have been a first step in aquatic adaptation before its loss."
Chimp Human Human
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Hedgehog
Humans
Whales
Monkeys
Number of adipocytes (fat cells)/log body mass (g)
Humans are extremely special primates/animals4. Fat
Morgan E. 1997. AAH
34Cunnane SC. 2005. Survival of the fattest. World Scientific, New Jersey
Humans are extremely special primates/animals4. FatCunnane: Our neonates are extremely fat: essential for brain development
35Cunnane SC. 2005. Survival of the fattest. World Scientific, New Jersey
Humans are extremely special primates/animals4. FatCunnane: Our neonates are extremely fat: essential for brain development
36Morgan E. 1997. AAH
Naked, fat, big: who else? 'Pachyderms' (Cuvier)And of course: whales and dolphins: + streamlined
+ streamlined
Humans are extremely special primates/animals4. Fat
Fully aquatic
Semi-aquatic
Aquatic relatives/ancestors
Terrestrial
Manatee
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An aquatic explanation for all this fatness and nakedness?
Fatness: Fat insulates best in water. Fat provides buyoancy (floating)
Hairlessness: Fur insulates by trapping air. Wet fur looses its insulation capacities
Nakedness increases streamline in water
An aquatic explanation for the food source that can provide all this [special] fat (8% of brain: omega 3): see 12. Large brains
Humans are extremely special primates/animals4. Fat
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Humans are extremely special primates/animals5. Our bodies are wasteful with water and are not adapted for large water intake at once:
1. Land animals concentrate the urine to save waterOur urine is not concentrated:
3. Heavy illness of humans at 3% water depletion Donkey, camel: only at 20% water depletion
4. Land animals drink large amounts of waterHumans need to drink often, but can only take in small amounts at the time
2. We sweat twice as much as camels, 5 times as much as horses (per surface of skin) Most land mammals do not sweat at all.
Species millosmol/l Niche
Beaver 550 Sweet water
Pig 1100 Marshes
Human 1400 ?
Dolphin 1700 Sea water
Cat 3200 Land
Cangooroo Rat 4600 Desert
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Humans are extremely special primates/animals5. Our bodies are wasteful with waterWe have multipyramidal reins, more like manatees than like apes
Marcel Williams. 2011. Chapter 8. WMMA?In this chapter, I argue that evolution of renal medullary pyramids in mammals is an adaptive response to diets with exceptionally high salt contents and that the existence of multiple renal medullary pyramids in humans was the result of specialized coastal marine adaptations in the human evolutionary past.
apes: unipyramidal reinshumans: 8-18 medullary pyramidsmanatees: 6-11 medullary pyramidswhales, dolphins: hundreds of pyramids
Camel/Manatee HumanApes
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Humans are extremely special primates/animals5. Our bodies are wasteful with waterSweating, crying and spitting
Sweating: Our sweat may initially have served for removal of salt:Salt content of sweat increases when eating more salt.
Secondary function (after returning to land): cooling
Land mammals cool by panting, which we can no longer do: as most aquatic mammals.
Crying: We are the only species with emotional tears: no explanation thus far.
Spitting: We are the only species (except camelidae) that spit.We spit especially during exercise, and when salty sensation in mouth.[Camels: drink brink water, eat halophytes: spitting is removal of salt?]
Whatever the explanation: sweating, crying and spitting = wasting water.Unlike desert or land animals.
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Humans are extremely special primates/animals5. Our bodies are wasteful with water
Our bodies are wasteful with salt as well:sweat, salty tears.
Advantageous when you are living in/at the sea
But problematic when you return to land: we crave for salt:Salzburg: salt minessalary: salt = money ('salarius')salt caravans
Moreover: Sea salt is iodine rich. We add iodine to salt
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Morgan E. 1997. AAH Schagatay. 2011. Chapter 7. WMMA?
Humans are extremely special primates/animals6. External nose and everted lips with a philtrum/mouth breathing
Seems maladaptive: the current of air has to describe a U turn before reaching the lungs.But: What if you dive, head first, or swim beneath the water:The nose acts like a prow, forcing the water to deflect on either side of it.If not, the water would be forced up into the nostrils, as would happen with chimp or gorilla.
Moreover, some people can close the nose by raising the upper lip: + philtrum (absent in apes) fits the nose septum!
Some can close the nostrils and lower the nose tip (nose musculature)
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Humans are extremely special primates/animals6. External nose and everted lips with a philtrum/mouth breathing
Most land mammals (including chimp & gorilla) are nose breathing:Nose filters/sterilizes airNose warms airNose moistens air
Before air is reaching the lungs
We are mouth breathers when excercising, speakingReason for throat infections, chronic bronchial disorders?
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Humans are extremely special primates/animals7. Voluntary breath control/Diving reflex
Hominids (chimp, gorilla), terrestrial mammals: only autonomous breathingDolphins, whales: only voluntary breathingHumans, seals: both autonomous and voluntary breathing
Aquatic explanation for voluntary breathing?holding breath under water (see also previous slides: closing nostrils)
breathing extra deep before divingbreathing faster after dive
Verhaegen M. 1997. In den beginne was het water.Schagatay E. 2011. Chapter 7. WMMA?
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Diving reflexWhen our forehead touches water, heart rate is reduced.Of course, when we swim or dive as well.
Schagatay E. 2011. Chapter 7. WMMA?
Humans are extremely special primates/animals7. Voluntary breath control/Diving reflex
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Diving reflex: heart reduction rate
Schagatay E. 2011. Chapter 7. WMMA?
Humans are extremely special primates/animals7. Voluntary breath control/Diving reflex
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Humans are extremely special primates/animals8. Reduced colour vision
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Olfactory capacities of Homo < Pan, Gorilla < other primates, tree dwellers, flying animals
< most land animals
Olfactory brain bulb ofWhales: almost absentHomo: < 1/2 of Pan, Gorilla (same body size) < 1/2 of baboon (body size: 20 kg)
Relationship to habitat (water, land, tree (air)) (Verhaegen M. 1997. In den beginne ...)° Well-developed in terrestrial animals: smell traces can be left long distance tracking of partners and predators
(even in absence of sound or vision) due to the wind direction (2D)° Reduction in primates, bats, birds:
In trees/air, odors are blown away quickly, are difficult to trace (3D)° Further reduction in Pan, Gorilla: their ancestors had semi-aquatic adaptations (?)° Further reduction in Homo: more pronounced aquatic lifestyle: frequent diving (?)° Complete reduction in fully aquatic animals: in water, smell has very little use.
Humans are extremely special primates/animals9. Reduced smell
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Raccoon(washing bear)
Humans are extremely special primates/animals10. Increased manual dexterity and tactility
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Somatosensory characteristics as (semi-)aquatic adaptations?
Our sensing abilities (touch: sensitivity of skin) equal those of apesEarly primates had already increased sensing abilities: life in trees
Located in postcentral cortex (areas 3-1-2) (PCC): 50% larger in Homo than in Pan, Gorilla
Size of the 4 regions (head, arms, legs and trunk (torso))° Pan, Gorilla: all 4 approximately equal° Homo: head: half of the PCC, of which half for mouth and throat arms: same as Pan, Gorilla, but almost exclusively for fingers and thumb legs and feet: reduced trunk: sameIn summary: Homo vs Pan, Gorilla: increased sensitivity, which is located in finger tops, lips and tongue
(Semi-)aquatic explanation?° Hands, fingertops vs feet:Pan, Gorilla: same size of PCC regionHomo: Cortex for sensitivity of the hands is five times larger than for feet as in e.g. the raccoon ('washing' bear!): senses objects under water with fingers
° Lips and tongue: suction feeding of aquatic food (shell fish) by Homo?
Humans are extremely special primates/animals10. Increased manual dexterity and tactility
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Humans are extremely special primates/animals10. Increased manual dexterity and tactilitySomatosensory areas in the brain:disproportianately large area for fingers and mouth
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Aquatic life as an explanation for the origin of manual dexterity and stone tool use?
Alister Hardy (1960):"It seems likely that Man learnt his tool-making on the shore.
One of the few non-human mammals to use a tool is the Californian sea-otter, which dives to the bottom, brings up a large sea-urchin in one hand and a stone in the other, and then, whilst it floats on its back at the surface, breaks the sea- urchin against its chest with the stone, and swallows the rich contents.
Man no doubt first saw the possibilities of using stones, lying ready at hand on the beach, to crack open the enshelled "packages" of food which were otherwise tantalizingly out of his reach; so in far-off days he smashed the shells of the sea urchins and crushed lobsters' claws to get out the delicacies that we so much enjoy today. From the use of such natural stones ,it was but a step to split flints into more efficient tools and then into instruments for the chase."
Hardy A. 1960. Was Man more aquatic in the past? New Scientist 7: 642-645.
Humans are extremely special primates/animals10. Increased manual dexterity and tactility
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Humans are extremely special primates/animals11. Sexuality: Face-to-face mating - Hymen - Menstrual cycle
Vaginal hymen: not in chimps (although present foetal).Present in some aquatic mammals
Lunar rythms of menses. Lunar cycles also in some fish, frogs, toads, crabs, seahorses ...
Streamline for diving vagina ventral face to face-mating: Also in aquatic mammals and (bonobo)
Underwaterbirth: proceeds smoother, with less distressWas discovered by accident (Odent M. 2011)
An example:
Odent M. 2011. Chapter 9. Obstetrical implications of the Aquatic Ape Hypothesis. WMMA?
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Species Brain size (g) Body weight male (kg)
Australopithecines 400-500 30-50
Chimp 400 45
Gorilla 500 170
Homo erectus (+) 860-1000 60
Homo neanderthalensis (+) 1420 76
H. sapiens, early (Cro Magnon)(+) 1500 63
H. sapiens, present 1350 60
H. sapiens, inuit 1500 60
H. sapiens, aboriginals 1250 60
H. sapiens, pygmee 1100 40
Humans are extremely special primates/animals12. Large brainsBrain size vs body weight in hominids
Compiled from Verhaegen M. 1997, Cunnane SC. 2005
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Eating fish and seafood such as salmon, halibut, tuna and scallops a few times a week is an easy way to increase your omega-3 intake. Plus you'll get all of the other nutritional benefits that these foods have to offer. http://www.whfoods.com/genpage.php?tname=george&dbid=75
Het zenuwstelsel heeft van alle weefsels in het lichaam het hoogste vetpercentage.
Volgens dr. David Horrobin, een pionier in het onderzoek naar essentiële vetzuren, bestaat ongeveer 8% van de hersenen uit omega-3-vetzurenDit houdt in dat omega-6- en omega-3-vetzuren in een evenwichtige verhouding tussen de 3:1 en 5:1 moet worden geconsumeerd. Onderzoek lijkt erop te wijzen dat de voeding van de oermens, rijk aan zeevoedsel, noten en andere omega-3-bronnen een dergelijke verhouding heeft verschaft.Een typisch westers voedingspatroon heeft een omega-6:omega-3 verhouding van tussen de 10:1 tot 30:1, dus dramatisch uit balans in de richting van omega-6-vetzuren. De meeste plantaardige oliën bevatten naar verhouding veel meer omega-6- dan omega-3-vetzuren. ***
Humans are extremely special primates/animals12. Large brainsAn aquatic explanation for large brains?
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Food source Fat percentage Arachidonic acid (AA)Omega 6
Docosohexaonic acid (DHA)Omega 3
Game lean, < 4% fatWart hog 8.5 0.6African buffalo 7 0.4Zebra 3.0 0.23Antelope 8 0.4Kangaroo 7.7 0.9Kangaroo liver, 4% fat 4 6.9 1.3Sea birdsPenguin liver 8.6 11.2Emperor penguin egg yolk, 30-40% fat 1.7 5.5Emperor penguin, maternal blubber 0.4 8.0
Temperate shell fish Mussel (Mytilus spp.) 1-3 2-4 6-14Surf clam (Spisula spp.) 1-3 4 11-12Quahog clamd, -1°C 3 1.6 13.1FishSand smelt 3.8 4.3 24.8Whiting 2.7 3.5 40.8Australian barramundi 0.3 14.5 16.2
Indian halibut 1.7 6.3 10.4
Broadhurst CL, Crawford M. 2011. Chapter 2. WMMA? Compiled from Tables 1 and 2
Humans are extremely special primates/animals12. Large brains
The structural, cognitive and visual development of the human brain strictly requires long-chain poly-unsaturated fatty acids (LC-PUFA), and the most important of these is docosahexaenoic acid (DHA). The mammalian brain is about 60% lipid, with high content of LC-PUFA in membrane phospholipids.The central nervous system uses omega3 (DHA) and omega6 (AA) almost exclusively
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1. Increased song capacitiesPrimate ancestors (cfr. gibbon)Aquatic life: Communicaton by sound, rather than by smell and vision
(cfr. whales, dugongs = Sirenes)
2. Increased control of oral apparatus and breath controlSea food: Suction feedingDiving for sea food: Voluntary breath control
1 + 2 Humans are extremely good singers Further development of vocal cords and breath control
3. Increased brain capacitySea food: Omega3, brain minerals (iodine)
3 + extreme song capacities SYMBOLIC LANGUAGE
13. Sea food, song and speechA possible aquatic explanation of why we can speak?Why is it only humans can speak? Current explanations:Steven Pinker: speech was advantageous. That is why it was selectedSteve Bickerton: a macromutation took placeNoam Chomsky: we have a language acquiring device: innate grammarVaneechoutte & Skoyles 1998: we have a music acquiring device
pre-adaptive for language (cfr. Charles Darwin?)
Vaneechoutte M, Skoyles J. 1998. The memetic origin of language: humans as musical primates. J. Memetics - Evolutionary Models of Information Transmission 2.
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Is knowing about our exact past history a purely academic matter?
Or has it e.g. medical consequences?
Descended larynx free uvula Sudden Infant Death Syndrome (SIDS) Sleep apnoea Chronic fatigue
DepressionExternal nose cartilage: cracks during birth deviated septaVarices We have special external venes. With age - standing upright too long: defectsBack ache (hernia)Ear exostoses: overall: 2%, swimmers: 43%. Frequent in H. erectus!Mouth breathing: Throat infections, chronic bronchial disordersSinuses: sinusitisAcne: sebaceous glands produce oily substance, for waterproofing hair and skin
become large and very active during puberty (<-> apes)Pregnancy problems: pre-eclampsia: due to conflict between mother and foetus
because pregnant women do not get the right food: sea food?Neonate problems: limited iodine intake: mental retardation, cretinism, ADHD
Verhaegen M. 1987. The aquatic ape theory and some common diseases. Med Hypotheses 24: 293-299. Morgan E. 1990. The scars of evolution. Souvenir, London.Morgan E. 1997. The aquatic ape hypothesis. Souvenir, London.
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My thesis is, of course, only a speculation - an hypothesis to be discussed and tested against further lines of evidence.
Such ideas are useful only if they stimulate fresh inquiries which may bring us nearer the truth.
Alister Hardy. 1960. New Scientist 7: 642-645
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There may be sound reasons why the aquatic model, like the savannah one, will in the end, after careful scrutiny, have to be abandoned.
But there is no case for rejecting it out of hand. Over the past ten years it has been adjusted and modifiedto meet valid objections and to accomodate new data.
For those who have assumed that there is something inherently untenable about it,it is time to think again.
Elaine Morgan. 1997. AAH. Page 20.
Are AAT adepts fanatics?
27/05/2011
Was Man more aquatic in the past?
Mario [email protected]
Marc [email protected]
May 27th 2011ECCOVUB
Slides downloadable at:http://users.ugent.be/~mvaneech/Vaneechoutte. 2011. Was Man more aquatic. ECCO. 110527.pptx
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The people along the sandAll turn and look one way
They turn their back to the landThey look at the sea all day
Robert Frost
Quoted by Elaine Morgan. 1997. AAH
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Was Man more aquatic in the past?Editors: Mario Vaneechoutte, Algis Kuliukas, and Marc VerhaegenBentham e-Books, 2011. ISBN 978-1-60805-244-8Foreword: ELAINE MORGAN1. PHILLIP TOBIAS. Revisiting water and hominin evolution2. C. LEIGH BROADHURST AND MICHAEL CRAWFORD. Littoral man and waterside woman: The crucial rôle of marine and lacustrine foods and environmental resources in the origin, migration and dominance of Homo sapiens 3. ALGIS KULIUKAS. A wading component in the origin of hominin bipedalism4. MARC VERHAEGEN, STEPHEN MUNRO, PIERRE-FRANÇOIS PUECH AND MARIO VANEECHOUTTE Early hominoids: Orthograde aquarboreals in flooded forests? 5. STEPHEN MUNRO AND MARC VERHAEGENPachyosteosclerosis in Archaic Homo: Heavy skulls for diving, heavy legs for wading?6. ALGIS V. KULIUKAS AND ELAINE MORGANAquatic scenarios in the thinking on human evolution: What are they and how do they compare? 7. ERIKA SCHAGATAYHuman breath-hold diving ability suggests a selective pressure for diving during human evolution8. MARCEL FRANCIS WILLIAMS. Marine adaptations in human kidneys9. MICHEL ODENT. Obstetrical implications of the aquatic ape hypothesis10. ANNA GISLÉN AND ERIKA SCHAGATAYSuperior underwater vision shows unexpected adaptability of the human eye11. WANG-CHAK CHAN. Human aquatic color vision12. MARIO VANEECHOUTTE, STEPHEN MUNRO AND MARC VERHAEGENSeafood, diving, song and speech13. RICHARD ELLIS. Aquagenesis: Alister Hardy, Elaine Morgan and the aquatic ape hypothesis14. TESS WILLIAMS. Just add water: The aquatic ape story in science15. ALGIS V. KULIUKAS. Rebuttal of John Langdon.
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