Discussion on hypothesized ancestral human cyclical ARC dive-foraging

[wet]

Early Humans Skipped Fruit, Went for Nuts : Discovery News

"Early hominid ancestors may have left the trees to take advantage of ground-level foods, a behavioral shift that could have resulted in two of the major defining characteristics of humans: unique teeth and walking on two legs, a mode of locomotion known as bipedalism that is extremely rare elsewhere in the animal kingdom."
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They started at wetland/woodland edges, bipedal wading/floating at surface, eating floating herbs (hydrocharis) and water lily/lotus/sedge rhyzomes/umbels, shellfish-crustaceans, bush berries and low hanging fruits (they always ate fruit but not much large tough fruit) and nuts.

Apes moved higher into rainforest canopy (100m) specializing on large hanging fruit (note their large incisor and canine teeth) but still getting swamp herbs, while human ancestors moved to more coastal seashore areas, adding more oysters, seafoods, and eventually fish and waterside ambushes as dive-foraging improved. Advent of improved technology allowed further expansion into other habitats.

 

[BennyB]

Moved to the Beach Bar. This is getting a bit off topic for the Freedive Science section.

Ben

 

[wet]

The Brain: relative size, speed & complexity of sensory system (including intra-specific communication): oxygen as catalyst, food as fuel

Tiny brains: "Insects may have tiny brains, but they can perform some seriously impressive feats of mental gymnastics. According to a growing number of studies, some insects can count, categorize objects, even recognize human faces — all with brains the size of pinheads. Despite many attempts to link the volume of an animal's brain with the depth of its intelligence, scientists now propose that it's the complexity of connections between brain cells that matters most...

Whales, with brains that weigh up to 20 pounds and have more than 200 billion neurons, are no smarter than people, with our measly 3-pound brains that have just 85 billion neurons. Instead of contributing intelligence, big brains might just help support bigger bodies, which have larger muscles to coordinate [Larger muscles aren't significant, see large herbivore dinosaurs with tiny brains] and more sensory information coming in.
Tiny insect brains can solve big problems - Discovery.com- msnbc.com
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Elephants and humans evolved similar solutions to problems of gas-guzzling brains : Not Exactly Rocket Science

Both humans and elephants show both semi-aquatic and terrestrial foraging traits, throw stones, manipulate branches or sticks, squirt water, live relatively long lives, have strong social behavior, have generally low rates of mutation yet high rate of mutations among specialized amino acids involved in "aerobic energy metabolism (AEM)" genes - which govern how mitochondria metabolise nutrients in food, in the presence of oxygen.

We already knew that the evolution of AEM genes has accelerated greatly since our human ancestors split away from those of other monkeys and apes (highly beneficial to a part-time sessile-benthic submersed forager (human ancestor, elephant ancestor) which needs both apneic and aerobic capability, but not a full-time pelagic dive chaser (dolphin) which needs maximal apneic (anaerobic) capability, nor a part-time wetland floating-food forager (congo swamp gorilla) which keeps its face always above water surface and so lacks apneic capability while not transiting far habitually so no selection for aerobic endurance.

"While other mutations were reshaping our brain and nervous system, these altered AEM genes helped to provide our growing cerebral cortex with much-needed energy.
And sure enough, elephants have more than twice as many genes with high ratios of non-synonymous mutations to synonymous ones than tenrecs do, particularly among the AEM genes used in the mitochondria. In the same way, humans have more of such genes compared to mice (which are as closely related to us, as tenrecs are to elephants). Overall, his conclusion was clear - in the animals with larger brains, a suite of AEM genes had gone through an accelerated burst of evolution compared to our mini-brained cousins. Six of our AEM genes that appear to have been strongly shaped by natural selection even have elephant counterparts that have gone through the same process.

Goodman's next challenge is to see what difference the substituted amino acids would have made to us and elephants and whether they make our brains more efficient at producing aerobic energy. He also wants to better understand the specific genes that have been shaped the convergent evolution of human and elephant brains over the course of evolution."
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Both elephants and humans are very water-dependent and not well conserving of metabolic fluids (unlike full-time savanna/marine dwellers), moving from waterhole/lagoon to waterhole/lagoon, foraging opportunistically along the way.
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Elephant ancestors were semi-aquatic - Telegraph
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Hominid Brain to Body size: Encephalization Quotient, estimated diet

5.8 Homo sapiens - grain-meat-nut-fruit-herb/tuber-seafood-eater, boats, cooking
4.0 Homo erectus (late) - berry/nut-tuber-seafood-meat-eater, simple spears-axes
3.3 Homo erectus (early) - berry/nut/tuber-seafood-eater, sticks-pebbles
3.1 H/A habilis - mixed diet? -nut-fruit-invertebrate eater?
2.9 Australopithecus robustus - tuber-nut-berry-herb eater
2.0 Pan t. (chimpanzee) - rainforest canopy fruit-honey-termite-meat-nut eater
1.7 Gorilla g. (gorilla) - herb-rainforest canopy fruit-hydrocharis eater

 

[wet]

Moved to the Beach Bar. This is getting a bit off topic for the Freedive Science section.

Ben

Neatorama!
http://2.bp.blogspot.com/_viHEhhBk2WY/SwFZumPMLfI/AAAAAAAAB8k/KrFUB468-OA/s1600/neatorama-front.jpg

Too big to eat!
Newseum | Today's Front Pages | The West Australian

Two monofins are better than one!
Newseum | Today's Front Pages | Kauno Diena
rofl

 

[TimoP]

Wet, He HAS other Ape roots than aquatic or savannah:



As you see, his ancestors have eaten fruits in high trees and nuts and mushrooms on high cliffs.
If his ancestors slipped and fell, they had a special mushroom diet treatment for injuries. Because they had found that just a fish oil didn't work in those cases.

If excess apnea did induce (temporary) brain damage, might fish oil (& other seafoods) repair the damage? Possibly compare to whales fishing at depth for parallel effects.

--------------------------------
Respect for Dan!
But don't try this yourself, it has extremely high and serious risks without ropes!
---------------------------------

 

[JennyWren]

Neatorama!
http://2.bp.blogspot.com/_viHEhhBk2WY/SwFZumPMLfI/AAAAAAAAB8k/KrFUB468-OA/s1600/neatorama-front.jpg

Too big to eat!
Newseum | Today's Front Pages | The West Australian

Two monofins are better than one!
Newseum | Today's Front Pages | Kauno Diena
rofl

wait....whut?

 

[Mullins]

Awesome video Timo. I'm sure he did it countless times with ropes before free climbing it and as with many sports the actual risk is usually a lot lower than it appears, but still.... that two-handed stuff is nuts.

However it's clear that the powder on his hands was from ground cuttlefish bones, which he could only have gathered by freediving. And most of his training would have been done underwater on sheer coral walls, to reduce the risk of injury. Have you seen the photo of Will Winram rock-climbing underwater?

 

[wet]

Islanding effects

Animal taxa stranded on small resource-poor islands often develop along two different paths:

1) inland non-aquatics tend to develop smaller brains and eyes, become more lethargic metabolically ectothermic (effectively cold-blooded) absorbing solar energy (galapagos tortoise, dodo bird), sustained on a low-quality/quantity diet.

2) shore-based part-time aquatics tend to develop larger brains and eyes used in aquatic foraging (seals, sea lions), become more lethargic metabolically ectothermic (hypothyroid symptoms) absorbing solar energy while resting ashore/afloat contrasted with active endothermic foraging.
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An islanded goat evolved "coldbloodedness" and delayed life span and small brain/eyes:
Physiological and life history strategies of a fossil large mammal in a resource-limited environment ? PNAS

Similar results in islanded dwarf hippos and mammoths, probably most often occurring when the surrounding water is cold or with fast currents.
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Archaic humans seem to have followed the second (calm warm seashore-based) path, although this has changed significantly in the last 100,000 years due to technology.

 

[wet]

wait....whut?

Hey JennyWren, thnx for staying on topic!

 

[TimoP]

I'm sure he did it countless times with ropes before free climbing it and as with many sports the actual risk is usually a lot lower than it appears, but still.... that two-handed stuff is nuts.

Yes, Dan probably knew the route . Maybe even could done a part of it eyes closed.
UW-climbing could be safer... or it depends on if the climber is an aquatic, savannah or high forest type. Maybe Will is mixed type?

After reading about AAH, Somali pirates have a new tactics:
Welcome to Facebook | Facebook

(Video is only in the FaceB, so maybe not all can see it:
Some freedivers walk upside down underwater in a line on the outside bottom of a ship )

JennyWren: wait....whut?

Today's front page is Yesterday's front page Tomorrow. I did't saw all the right pages either (in time). I think that's not a big loss.

 

[wet]

yesterday's news is like
footprints in the sand
after the tide turns

apes do not dive
monkeys do not backfloat
sea otters do both every day

Convergent parallels

 

[TimoP]

apes do not dive
monkeys do not backfloat
sea otters do both every day

Ok, I see, so this is the hard core of the AAH.

 

[wet]

[Note to a colleague]

Hello (...)

Do you have an opinion on these?

Chromosome 2 is unique to humans amongst hominoids, it contains the genes/SNP (Single Nucleotide Polymorphism) for:
- Photic sneeze (O2/CO2 regulation)
- Hypothyroidsm (Iodine regulation)
- Hemochromatosis (Iron regulation)

I do not view that as mere coincidence.

Regarding baby backfloating in warm sunlit lagoons:
Human babies have full envelope of SC white fat (insulatory)
but dorsal brown fat, which provides warmth to the only sun-shaded area that also is exposed to the coolest proximal water, infants don't shiver for warmth (not useful in water). Breastfeeding human infants produce/accumulate Hydrogen (most buoyant material) in the gut, and this, combined with (otherwise healthy) infant colic (GI gas entrapment while backfloating and associated crying) and abundant white SC fat, would provide sufficient buoyancy in dense warm calm saltwater to allow parental foraging without hindrance, in part resulting in loss of fur coat.

Regarding human endurance locomotion: At lagoons, dive foraging would be typical, but in between lagoons, shoreline walking/wading/jogging would be typical due to hazards of diving in rough surf. This was maintained during inland seasonal migrations where diving was limited.

Regarding islanding: I think that similar to how Gibralter functioned as a gateway for EurAsian macaques into north Africa, I think the Afar-Eritrea-Yemen region functioned as a gateway to and from EurAsia. The 'bridge' linking Yemen is about 100m deep, about the depth of sea level drop at various glacial periods, (disregarding lack of data on local tectonic changes). I do not view the Danakil alps region as "the refuge", but rather as a periodic gateway, similar to Gibralter and Sinai.

I haven't found any evidence to contradict the dark adaptation-dive / sunlight surface exhale idea (Aquaphotic Respiratory Cycle), except that it is not used today by modern human divers. I consider it plausible that during the MSC human ancestors separated from the other apes due to being trapped in the drying Medit. basin, where a unique environment produced selection for a unique hominid different from the others. The low UV present, similar to today's Dead Sea, may have selected for light skin tone or less fur, and unusual eyes (exposed white eye sclerae), and plausibly the sun sneeze, and also increased availability of stone, both for tools and climbing. Later filling of the basin would send various human-types in different directions, to adapt to local conditions with different morphotypes, many would go extinct later.

DDeden

ps. I've stepped away from AAT yahoogroup for a bit, but continue to skim the threads.

 

[wet]

http://www.nytimes.com/2009/12/01/science/01obpuff.html?partner=rss&emc=rss

Skin senses, distinguishes sound

Feel the noise : Nature
When we listen to human speech we use a combination of the senses: the ears, obviously, and the eyes to see how a speaker's face changes the perception of consonant sounds. Experiments seeking to add the sense of touch to the mix have until now been inconclusive. Many languages use an expulsion of air to change vowel or consonant sounds — in English to distinguish a sound like 'da' from the microphone-popping 'pa'. Bryan Gick and Donald Derrick take that 'puff of air' as the starting point for a study of whether the sense of touch can contribute to what we 'hear'. They applied small, inaudible air puffs to the skin of volunteers who were simultaneously listening to a series of consonant sounds. Air puffs aimed at either the hand or neck made it more likely that aspirated sounds would be heard.
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Sound travels much faster through water than through air. Humming does not produce puffs, nor does clicking. Consonants are uniquely human, and may have derived from tonal-clicks, as in the click consonants of the Khoisan languages. Similarly, tonal languages (Chinese, Khoisan) may have derived from combining hum tones with softened clicks and glottal stops.

Humpback whales, Jamaican tree frogs (no throat airsac), wrens, gibbons and mice all have humming "song" of changing tone.

Dolphins, bats and cave swifts all have clicking buzzes of changing speed (rhythm), sub-aquatic frogs and humans can produce clicks (no throat air sac) but not high-speed buzzes.

Great apes, especially the close genetic relatives, the chimps, have pant-hoots, which separates nasal breathing from air sac vocalizations, similar to pond/swamp frogs (croaking with inflatable throat air sacs), all typical of float-foragers, not dive-foragers. Backfloat-divers do not produce pant-hoots.
Pant-hoot (call) - Wikipedia, the free encyclopedia

 

[DivingDane]

oh dear this thread is still stumbling along????? why?

i have no problem with any belief system i only have a problem with people who insist on pushing it upon others.

i have Jehovahs witness friends (theyb started my life in Freediving) but are aware that i do not wish to be apart of the faith and leave it at that. even the other faiths which insist on knocking on my door now know that i am not interested.

so why continue to post random information without any reasoning or explanation here?

i know none of us have to actually open this thread to read it but really why do you continue to dribble.

this could potentail be a very realistic (if slightly romantic idea of our origin) but the manner in which you relay the information reminds me very much of how the majority of scientolgists Z(the ones i have met) release their "doctorin"

Stating the idea then laying out clear scientific proof which is related to the idea not pulled from obscure texts, would help to turn this around.

information tht would be accepted in a university or place of higher learning would also be beneficial. scientific journal accepted arrticles are always good for this.

but PLEASE stop the dribble and make some sense ith this thread.

DD

 

[wet]

this thread

Another DivingDuck...?

Turtles (or ducks?) All the Way Down | North Coast Journal | Humboldt County, Calif.
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How our skin helps us to listen : Not Exactly Rocket Science

To continue on sensorial awareness, skin as "hearing" organ:
"the integration of hearing and touch isn't surprising - both senses involve detecting the movement of molecules vibrating in the world around us... also worked on the back of the neck, which is much less sensitive (than fingertips) and unaffected by our own spoken breaths".

Backfloating while communicating with submerged dive partner, the back of the neck and the earlobes (much longer in humans than in apes) have sensory receptor nerves able to detect molecular vibration (sound in calm water), as well as the temperature of the water at the surface and at depths just below the surface.

While wading in deep rough water, not facing the oncoming waves, the back of the neck and earlobes also inform the size, speed and relative temperature of the waves. While non-wading non-backfloating seals have lost their pili muscles (which lift the fur to a fluffy position), humans have retained these pili muscles despite losing the fur coat, resulting in sensitive goose pimples which don't warm but do inform of water temperature and speed.

While at depth in sunwarmed calm lagoons, color vision with blue shift, fast dark adaptation, visual accomodation skill, skin sensitive to vibrations/temperature, ability to communicate with dive partner with both sight and sound, etc. would be advantageous.
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Is there anyone at Deeper Blue that backfloats and dives?

(wait for this one, on backfloating, (diving), sensory processing)
Giving Thanks | North Coast Journal | Humboldt County, Calif.
eyes: 10,000,000 bits per second
skin: 1,000,000 bits per second
ears/nose/tongue: 200,000 bits per second
mind: filters out all but about 40 bits per second prior to awareness

Reduction of acoustic startle response & vertical climbing in human ancestors, not chimps, via genetically modified mice:
N-Glycolylneuraminic Acid Deficiency in Mice: Implications for Human Biology and Evolution -- Hedlund et al. 27 (12): 4340 -- Molecular and Cellular Biology

Acoustic startle reflex: in air, humming reduces incoming sound, but in water humming does not reduce incoming sound, due to skin/bone conduction.
[ame=http://en.wikipedia.org/wiki/Acoustic_reflex]Acoustic reflex - Wikipedia, the free encyclopedia[/ame]
"The stapedius reflex (in air) is also invoked when a person vocalizes. In humans, the vocalization-induced stapedius reflex reduces sound pressure levels reaching the inner ear hair cells by approximately 20 decibels."

Happy Thanksgiving to anyone celebrating it.

 

[wet]

Parachuting whales have a BIG mouthfull

From worm to whale: form, scale in hydro/aero/thermo- dynamics/statics
How size scaling affects locomotion, digestion, respiration, flight, foraging method...

"Goldbogen and his colleagues found that big fin whales are not just scaled-up versions of little fin whales. Instead, as their bodies get bigger, their mouths get much bigger."

"This (size) scaling may explain some of the weird diving patterns found in lunge-feeding whales. Blue whales are twice as big as humpback whales, for example, but both species dive for the same period of time (about eight minutes) and to the same depth (148 meters). All things being equal, you’d expect that blue whales would be able to dive deeper and longer, because they could store more oxygen in their bigger bodies. Blue whales also make fewer lunges than humpback whales (6 versus 15). It’s possible that the gigantic blue whales are hard up against a size limit. They need so much energy for their lunges that they can’t afford to hold their breath longer, and they can only manage to make a few lunges before they run out of reserves and have to head for the surface."

The Origin of Big | The Loom | Discover Magazine
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On Being the Right Size
h/t Razib @ GNXP
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Humans can suction feed on mollusks while submersed (eg. using a sharp chert flake to remove an oyster from the shell), and humans do have wider open (but not taller) mouths than apes, with muscular cheeks and piston-like tongue, I see no sign of lunge feeding as in the baleen whales, although humans are able to swallow small live fish whole (eg. goldfish).

 

[Arjen]

information tht would be accepted in a university or place of higher learning would also be beneficial. scientific journal accepted arrticles are always good for this.

No, that is so old school. No one does science like that these days. Did you not get the notice?

but PLEASE stop the dribble and make some sense ith this thread.

And ruin all our fun? Please no! I need it for my daily dose of madness. And to get a few good laughs of the good recaps that others make from time to time.

 

[wet]

Breath-hold champs: Naked Mole Rats - 30 minutes (virtually cold-blooded hairless social rodents which live in underground colonies for 20 years)
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Naked mole rats may hold clues to surviving stroke
"Two University of Illinois at Chicago researchers report in the Dec. 9 issue of NeuroReport (now on-line) that adult naked mole rat brain tissue can withstand extreme hypoxia, or oxygen deprivation, for periods exceeding a half-hour -- much longer than brain tissue from other mammals. But naked mole rats studied were found to show systemic hypoxia adaptations, such as in the lungs and blood, as well as neuron adaptations that allow brain cells to function at oxygen and carbon dioxide levels that other mammals cannot tolerate. "In the most extreme cases, naked mole rat neurons maintain function more than six times longer than mouse neurons after the onset of oxygen deprivation," said Larson. "We also find it very intriguing that naked mole rat neurons exhibit some electrophysiological properties that suggest that neurons in these animals retain immature characteristics."

All mammal fetuses live in a low-oxygen environment in the womb, and human infants continue to show brain resistance to oxygen deprivation for a brief time into early childhood. But naked mole rats, unlike other mammals, retain this ability into adulthood.

"We believe that the extreme resistance to oxygen deprivation is a result of evolutionary adaptations for surviving in a chronically low-oxygen environment," said Park. "The trick now will be to learn how naked mole rats have been able to retain infant-like brain protection from low oxygen, so we can use this information to help people who experience temporary loss of oxygen to the brain in situations like heart attacks, stroke or drowning," he said.
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Loss of fur = increase in skin sensors = more neurons & myelination?, Development of Q-Hetero-Chromatin in African hominoids, increased in Human line.
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(h/t FL@AAT)
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After lesser apes (gibbons) split away, other hominoids developed larger body, nest building, harem-group socialization, sexual dimorphism traits, inner fur lost but retained laryngeal air sacs and outer hair and did not favor dry forests (later pliocene drier climate produced knucklewalking in inland gorilla & chimps, not in coastal dive-foraging hominins)

Did increased gene duplication set the stage for human evolution?
"... For example, a duplication observed in orangutan, chimpanzees, and humans but not in macaques must have occurred sometime after 25 million years ago but before the orangutan lineage branched off [size dimorphism, nests, inner fur?]. Eichler's research team found an especially high rate of duplications in the ancestral species leading to chimps and humans [more meat/nuts in diet, simple stick-stone use, reduced canopy-top & water-surface foraging, drier period] even though other mutational processes, such as changes in single DNA letters, were slowing down during this period. "There's a big burst of activity that happens where genomes are suddenly rearranged and changed," he says. Surprisingly, the rate of duplications slowed down again after the lineages leading to humans and to chimpanzees diverged ..." [humans east of Africa, chimps at eastern Africa 5ma-2.5ma, then both moved west, humans to Rift, chimps to Congo]
_____

T Marques-Bonet ... Eichler 2009 Nature 457:877-881 doi 10.1038/nature07744
A burst of segmental duplications in the genome of the African ape ancestor

"... We find that the ancestral branch leading to human and African great
apes shows the most significant increase in duplication activity both in
terms of base pairs and in terms of events ... We discover striking examples
of recurrent and independent gene-containing duplications within the gorilla
and chimpanzee that are absent in the human lineage ..." [knucklewalking, congo parasites, reduced canopy & water surface foraging & darker fur (eagle & mosquito-malaria predation?)]
(H/T MV@AAT)

 

[wet]

Lund University, Malm, clues in the lagoons, Fisheries
English:
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Lund University, Abrahamsson
Swenske:
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