Wednesday, November 30, 2011

Humans & Huts, Apes & Nests, Monkeys & Masses

'Conch-shell' dome hut of bamboo and rice straw:

77ka bedding with insecticide:


56ma- Opposable big toe/thumb allows clinging to twigs, (no claws for
trunk climbing, no lemur leaping)

52ma- Noct to diurnal, increased sociality (group noct. sleep, less insectivory, more leaves & fruit)

35ma- OWM/apes got color vision (canopy sleep - snakes-raptor detection,
more frugivory)

23ma- TRP2 pheromone signal disabled (olf. neural switch to RAM?),
increased visual sexual signaling in hominoids

20ma- Morotopith vertebrae - orthogrady, twig weaving bowl nests (all
extant great apes) anti-raptor mimicry

16ma- family coherance/bonding - increased altriciality & neural complexity?

50ma: nocturnal slow-climbing insecti-folio-frugi-omni-vorous, scent-dominant (slow-loris -like)primates become diurnal/social binocular-color-sight-sound dominant, night-sleeping in plucked-leaf-cushioned tree-forks or enmassed-bunch ("snoozing-bear" mimic) defence against predators.

Opposable thumb allows clinging to twigs, sharp nails grasps trunks:
A 56 MILLION-YEAR-OLD skeleton found in Wyoming shows that one of the
earliest primate ancestors had an opposable big toe, allowing it to creep
to the outermost branches of trees to hunt nuts and fruit.

Because Carpolestes combines features of the earlier plesiadapiforms with
primate-like features, it begins to answer the question of what order these
traits evolved, and for what purpose. The study is published in the November
22 issue of the journal Science. ...
The Carpolestes, which weighed about 4 ounces (100 grams), had a long tail,
and a body about 14 inches (35 centimeters) long, shared some, but not all of
the characteristics of modern primates, and thus can be viewed as a
transitional animal. It had very primate like teeth that were highly
specialized for eating flowers, seeds, and fruit. The opposable big toe gave
it a grasping ability that indicates it spent most of its time climbing trees.

Carpolestes also had a nail on its big toe, but its eyes were not forward
facing, and it did not have the bone structure that would allow for
specialized leaping, like some of the earliest primates.
The team pinpointed the shift from non-social to social living to about 52 million years ago; a switch that appears to have happened in one step, and coincided with a move into daylight.

An analysis of over 200 primate species by a University of Oxford team suggests that our ancestors gave up their solitary existence when they shifted from being nocturnal creatures to those that are active during the day. It is likely communal living was adopted to protect against day time predators, the researchers say.
"If you are a small animal active at night then your best strategy to avoid predation is to be difficult to detect," explained Oxford's Suzanne Shultz, who led the study.

"Once you switch to being active during the day, that strategy isn't very effective, so an alternative strategy to reduce the risk of being eaten is to live in social groups," she told BBC News.

Dr Shultz thinks that the move to day-time living in ancient primates allowed animals to find food more quickly, communicate better, and travel faster through the forest.

female bonding emerged much later at about 16 million years ago.
35ma- OWM got color vision but lost pheromone detection (replaced by RAM?)

Even our humble mammal cousin, the mouse, was found to have 140 genes just for pheromone receptors when its genome was completely sequenced earlier this year.
But humans are clueless when it comes to pheromone signals, according to University of Michigan evolutionary biologist Jianzhi “George” Zhang. He believes color vision put our pheromones out of business.

Zhang said. In fact, though humans and these apes still carry genes that should create pheromone receptors in our noses "Some pheromone detection genes don't function. There is considerable evidence that there are nasal receptors for pheromones in humans which affect behaviour, though their signals are not registered consciously." This may be origin of RAM memory in humans, via olfaction neural network.

A pheromone attaches to a water molecule, drifts about in the air currents and finally lands on the proper receptor in someone else’s nose. The receiver can’t immediately be sure who sent it, where it came from or when. But with sexual swelling, everyone in the troop can see precisely when and where the signal is, even at a significant distance.

Sexual swelling occurs in about 10 percent of all primate species, but only in the Old World species of Africa and Asia, which is where humans probably originated, as well.

To test their idea, Zhang’s team zeroed in on a human gene called TRP2, which makes an ion channel that is unique to the pheromone signaling pathway. They found that in humans and Old World primates, this gene suffered a mutation just over 23 million years ago that rendered it dysfunctional. But because we could use color vision for mating, it didn’t hurt us. In turn, the pheromone receptor genes that rely on this ion channel fell into disuse, and in a random fashion, mutated to a dysfunctional state because they haven’t experienced any pressure from natural selection.

34ma: New World monkeys transit Atlantic Ocean on floating vegetative raft, Red Sea opens, Antarctica freezes, equatoreal-Tethys currents changing affects forest seasonality.

20ma: Hominoids become sub-canopy open-bowl-nesting (eagle-nest mimic, outreached hooked hand = raptors' hooked beak, red scalp hair = danger sign to predator in flight, infant coo-ing = eagle chick cheeps), orthograde upright branch-hanging/standing/hand-plucking apes eg. morotopithecus, ardipithecus; development of deeper larynx and laryngeal air sac improved both upright vocalization in rainforest canopy and face-up upper-body buoyancy while wade-foraging (cf finger-raking surface-growing hydrocharis seaweed by Ndoki gorilla) in shallow forest wetlands and coastal mangroves, some slow open-ground upright bipedalism (cf siamang) with only little (above-branch) pronograde quadrupedalism.

5ma: Chromosome 2 inversion/fusion [Photic sneeze reflex activated, Iodine & Iron metabolism changes] in human ancestors, humans invert (dimple) the standard woven great ape sub-canopy open-bowl nest (leaf-lined interior) into small fully-enclosed-dome-hut with mosquito-proof/waterproof leaf-shingled exterior (reduced natural selection for fur coat), entire dome was lifted for access. Photic sneeze was advantageous against predation, eg. a leopard (or human enemy) at daybreak lifting the dome shell would flood it with sunlight, causing an explosive solar-powered sneeze (accompanied by a sharp stick) in the snout.

3.3ma: Gorilla louse transferred to humans and became human pubic louse, (possibly indicating that African Australopiths (eg. Lucy) starting at that period were HG hybrids?), Africa tropical rainforest reduced, humans more waterside and ground based. Apes (chimps, gorillas) independently develop knuckle-walking quadrupedalism to transit more open woodlands, while bipedal humans develop kneecrawling to enter/exit dome huts (no doorways yet, just lightweight dome shell).

2.6ma: First Oldawan sharp stone tools used to cut sedges/wicker/nuts/meat, reducing need for large sharp teeth, but molars enlarged for more chewing. Air sacs gradually lost, with increased submerged-face foraging (wading/swimming) in shallows for benthic rhyzomes and soft shelled seafoods along with shrub berries, herbs, eggs, larvae, etc.

1.8ma: Humans forage more often in coastal areas, develop denser bones and paranasal sinuses as result of deeper benthic gathering of shellfish, crustaceans. Females made slightly larger domes to contain small infants while foraging nearby so as to keep both hands free, males made smaller portable domes as hunting blinds/roundshields which females valued for use as baskets, these roundshields may have covered open hatchways at night to signal female's domes companionship. Likely seafoods, mangrove honey and mangrove salt-crystal leaf exudates were collected, consumed and brought inland seasonally, perhaps exchanging with inland groups. Bifacial hand axes were improved for cutting, used as bait traps when inserted into fish or animal organs to bait crocs, bears, big cats & wolves near shore.

120ka?: Humans invent portable roundshield-door-roundboat, modify hut (cone & drum), add doorway hatch.

25ka?: Humans invent orthogonal linear buildings, villages evolve from seasonal camps

Article from New Scientist:

After a hard day hunting and gathering, humans 77,000 years ago could count on a good night's mosquito-free sleep on a comfy bed of grass and leaves. Archaeologists have discovered the oldest evidence of humans using plant bedding, 50,000 years before it appears anywhere else.

Many animals make beds for themselves, says lead author Lyn Wadley of the University of the Witwatersrand in Johannesburg, South Africa, but what's interesting in the new find is the way the owners managed their bedding. To keep it clean and pest-free, they burned it.

Wadley's team has spent the past decade excavating a rock shelter called Sibudu, situated high in a cliff surrounded by forest and near the Uthongathi river in South Africa. People lived there on and off between 80,000 and 38,000 years ago, in a complex society that used stone tools and even made glue and simple ornaments.

Wadley found layers of plant material on the cave floor that date from 77,000 years ago onwards – mostly grasses, sedges and rushes. These could not have grown in the dry shelter, so people probably collected them near the river.

Burning the beds
Wadley thinks the bedding was used to make a clean area for sitting, working, eating and sleeping. Tools and other artefacts were found buried within it.

Intriguingly, all the layers of bedding that are 73,000 years old or younger show signs of burning, which Wadley suggests may have been the result of routine cleaning. Burning the plants would have killed pests and diseases. That the cave's occupants needed to do this, he says, may suggest they spent extended periods of time in the shelter, so had to keep it clean.

It seems the bed-makers were selective about the plants they would sleep on. A range of trees grow in the region, but only the Cape laurel (Cryptocarya woodii) was used.

Cape laurel leaves give off insecticidal chemicals, so they would have repelled insects and their larvae – including malarial mosquitoes. That would make the cave bedding the earliest evidence of humans using medicinal plants, although other animals have similar tricks: common starlings often use insecticidal plants in their nests to repel blood-sucking insects.

Old knowledge
The behaviours may have started sooner than this site shows. "I would guess that right back until the earliest anatomically modern humans, people would have known which plant to choose," says Wadley.

Chimpanzees also build nests, and there is some evidence that they too include insecticidal plants. Fiona Stewart of the University of Cambridge, UK, spent several nights sleeping in chimp nests, and found that insects bit her less than when she slept on the ground.

"Perhaps this purpose of bedding has been continuous throughout human evolution," Stewart suggests.

Journal reference: Science, DOI: 10.1126/science.1213317

Note: I have written in an earlier post about medicinal and insecticidal plants used by archaic humans.

A bedding dated from the Lower Paleolithic, 130 000 years ago, was discovered by
Henry de Lumley. It was the home of the Lazaret Man near Nice in southern
France. The site was a construction, eleven feet long and twelve feet wide,
consisting of a frame of vertical posts resting against the wall of the cave, on
which were arranged skins falling to the ground. A partition separated the
interior activity areas and one area was containing the remains of a bedding.
The men of the Lazaretto rest and sleep on thick litter of dried kelp.

1) 52ma from noct to diur primates -> social group (little/no aquatic
foraging, surface swim)

2) 20ma from branch to open nest, prono to orthograde locom./forag.
(wade, face-up float, surface forage)

3) 5ma phot. sneeze reflex - from open nest to dome, (subsurface

4) 100ka-50ka roundboats (super-surface forage)

5) 20ka? longboats dugout/tied raft

My time chart:

0) pre-52ma small primate size, individual/infant tree hollow sleeping
(bushbaby, tupaia), little surface swimming

1) 52ma from noct to diur primates -> social group (little/no aquatic
foraging, surface swimming) (group sleeping on branches?(proconsul))

2) 20ma from branch to large open nest, (morotopith, raptor-mimic
nest) from prono to orthograde locom./forag.
(wade, face-up float, surface forage)

3) 5ma phot. sneeze reflex - from open nest to dome, (subsurface
forage, HP split, #2 chrom. fusion)

4) 100ka-50ka roundboats (super-surface forage) qufa

5) 20ka? longboats dugout/tied raft


Chufa = suph = sedge

Chum: Chinook - dog salmon, Siberian - cone tent (proto-tipi) for summer fishing?
Ket/a: Russian - dog salmon, Ket people of Yenisei R,
Kot/a: Saami/Lapp conic tent, Kot people of Yenisei R.