Monogamy in humans, hominoids and tree frogs
here

Air sac in a puddle frog species used for visual gesture more than vocalization, probably due to a 'tuned-in' aural predator abundance similar to Hawaiian crickets which lost their song due to predation:
here

Some frogs lack vocal sacs, such as those from the genera Heleioporus and Neobatrachus, but these species can still produce a loud call. Their buccal cavity is enlarged and dome-shaped, acting as a resonance chamber that amplifies their call. The noise of flowing water overpowers any call, so some river frogs communicate by other means.

The main reason for calling is to allow males to attract a mate. Males call either individually or in a group called a chorus. Females of many frog species, for example Polypedates leucomystax, produce calls reciprocal to the males', which act as the catalyst for the enhancement of reproductive activity in a breeding colony.[39] A male frog emits a release call when mounted by another male. Tropical species also have a rain call that they make on the basis of humidity cues prior to a rain shower. Many species also have a territorial call that is used to chase away other males. All of these calls are emitted with the mouth of the frog closed.

A distress call, emitted by some frogs when they are in danger, is produced with the mouth open, resulting in a higher-pitched call. The effectiveness of the call is unknown; however, it is suspected the call intrigues the predator until another animal is attracted, distracting them enough for its escape.

Many species of frog have deep calls, or croaks. The English onomatopoeic spelling is "ribbit". wikipedia

Nature by number: spatial geometry in natural growth patterns

here

New apith skeletons found

Friday, July 3, 2009

Aquatic frog of the Congo

The African dwarf frog, a member of the Pipidae, is an aquatic animal living its life entirely underwater, but needs to rise to the surface to breathe atmospheric air because they have lungs and not gills. They "breathe" water in through their skin. They are fairly small in size and don’t weigh more than a few ounces. (Wikipedia)

They produce vocal clicks and trills, rather than the more typical croaks of more terrestrial/arboreal frogs, due to a lack of long extensible tongue and throat sac.


Jamaican tree frog lacks vocal sac yet vocalizes
"Hyla marianae lacks a vocal sac" yet calls during mating season in arboreal wet bromeliads.
Treefrog without throat sac

So we see a precise parallel regarding water & foraging:
benthic foraging frogs & humans lack throat sac, lack tail
surface foraging frogs & large apes have throat sac, lack tail
arboreal foraging frogs & canopy gibbons lack throat sac, lack tail

benthic foraging salamanders & monkeys lack throat sac, have tail
arboreal foraging salamanders & *monkeys lack throat sac, have tail
*atellid howler monkey.
all wading/swimming/diving monkeys have medium or long tails.

---

Clicking for echolocation by dolphins and humans
http://www.wired.com/wiredscience/2009/06/echolocation/

Frog hydrodynamic streamlining:
Not linear in their resting position, no, but well streamlined and linear at
times when leaping and swimming.
http://www.funfacts.com.au/images/leaping-frog1.JPG
http://www.northrup.org/Photos/frog/low/frog-swimming-underwater.jpg

The frogs legs can spread wide, then clap together while pushing against the water.
http://t3.gstatic.com/images?q=tbn:oTBfOGA5itQV5M:http://afrogpond.com/files/motorbike-frog-eaparry.jpg

Some frogs/toads walk or gallop briefly rather than hop. Many treefrogs mostly climb on 4 limbs, boreal toads tend to walk more than hop on the ground. The natterjack ground gallops briefly on all four, and burrows into drying salt-mires with forelimbs initially and then rear limbs.
http://scienceblogs.com/tetrapodzoology/2009/10/natterjack_life_and_times.php

This parallels primates/hominoids again, the change from ancestral long-tail locomotion (monkeys/salamanders) to non-tail hydrostatic foraging results in modified locomotion (leaping/swinging) which in some species returns to near-ancestral qpal locomotion in some species (natterjack/knucklewalking apes). The only missing parallel remaining is the possible frog which developed bipedal gait, so far not found in nature. Possibly long-tailed proto-archosaurs (ancestors of crocs, T rex, birds) developed from a coastal arboreal salamandrid, which in the avian line lost the long tail after branch vertical perching and reversed toe evolved.

Parallel convergence

Sit float feeding in warm water -> hominoid, absent tail, air sac

Sit grass feeding on dry ground -> gelada, long tail, no air sac


Sit float feeding in warm water -> LCA toad/frog, throat sac, croak, long
prehensile tongue, rear feet similar to other frogs

Dive & swim in water -> diving frog, no throat sac, no croak, trill, no more
long prehensile tongue, rear feet differs from other frogs
Diving frog
This most-aquatic frog has a unique immunity to the fungi that is killing
amphibians around the world. Breath control.

Dive & swim in water -> human, no throat sac, no croak, speech/click
no prehensile toes, rear feet differs from other hominoids
Diving hominoid
This most-aquatic hominoid has a unique condition (domestication) that is
killing hominoids around the world. Breath control.

Parallel convergence among tetrapods.

-

Orang-utans: Our Closest Relative?

Lluc

I find it odd that Lluca was pictured as a flat faced orangutan, considering
that it is the most distant of all hominoids from the current location of the
orangutan populations. Yet if it was merely the westernmost kin of a ring
species of base Pongid-Hominid apes which distributed along the Tethys shores
with localized dietary and predatory adaptations, and varying degrees of
bipedality, it is not so surprising.

IMO the question is not "are humans and orangs most closely related?" but
rather, "why do people insist on placing human ancestors geographically next to
chimps and gorillas, despite the gross differences in morphology?". Two closely
related species living in the same environment do not change drastically their
morphology, see gorillas and chimps.

Since lowland gorillas forage for floating AHV in brackish water, mountain
gorillas forage in highland fog forests for ground THV, savanna chimps forage in
open woodlands, forest chimps forage for small invertebrates in shallow water
and rainforest bonobos forage in the sub-canopy, we know that human ancestors
must have done something different (or in addition) to account for the extreme
morphological changes.

Crocs and hippos dominate the tropical waters of Africa except for small puddles
and highland waters, notably they lack both fur and SC fat, like manatees, they
rely on the sun's warmth in shallow water. Beavers and otters have thick fur and
live in sub-tropical and temperate waters, with the habit of cool water diving.

Humans, unlike all other great apes, fit in between these two groups, sun
basking (ashore and afloat in warm water) and cool-water deep-diving (deeper
than body length).

That this would have developed after the Orangutan had split eastwards and the
African apes split westwards, seems most parsimonious. The human ancestor seems
to have done neither, until they had well adapted to and dominated their new
African and Asian niches.

Rather, human ancestors seem to have paralleled the crab eating macaques (and
possibly Allen's swamp monkey), foraging both at the shoreline and beneath the
water surface, but still retaining the primate ability to climb. (also
paralleling the African clawed frog and marine otters, which can climb but not
as well as treefrogs or stoats.)

Why would human ancestors have generally stopped climbing and hanging from tree
branches and reeds while foraging? Because they brought their sticks with them
into the water to get food, just as chimps bring customized sticks to spear
bushbabies, to gather termites, to collect honey, to dig tubers in the wet
season. Orangutans don't customize sticks, though they use twigs to get neesia
seeds from spiny fruit, using their lips since one hand and both feet are used
to keep them in position in the high forest canopy.

Human ancestors didn't need their hands and feet to keep in position in the
canopy, because the canopy was low at shorelines, and because the food was as
much under the water surface as above, including later ambushed prey.


I can think of an interesting parallel here, whereby the young and old males
both compete individually and cooperate societally,

Gorilla: young lighter males climbing to canopy, older large males actively
ground foraging and in bais shallows

Orangutan: young lighter males climbing to canopy to forage, older larger males
lower (and if no cats) on ground foraging in swamps.

Aquarboreal ape: young males more mobile fruit foraging, older larger males at
tidal waterside peeling mangrove oysters and papyrus.

He: young males climbing coconut palms, older larger males more in water diving
for longer periods.

Hn: young males in waterside trees leaping onto and stabbing thirsty animals
into the water, older larger fatter males backfloating camouflaged with long
spears aimed at the prey's throats and chest as they dash into deeper water away
from the airborne ambush.

Hs: young trim males as paddlers/sailors/fishers, older larger males as ship
builders/captains/bankers.

A bit simplified but interesting. Not sure what happened to the "harem" and size
dimorphism, seems variable depending on climate, but otherwise a sort of
continuum. I'd think the shoreline would make for weaker harem/dimorphism
societies than the inlands where drought would be more drastic. The very deep
diving elephant seal harems seem to contradict this, but that may be due to
quite different constraints (simultaneous birthing, cyclical food supply) than
an aquatic ape (with hidden estrus and year around birth) which could forage
above, below and along the surface, and travel far inland during the muddy
coastal rainy season.

Bio-convergent parallel: Anuroid & Hominoid

Arkive Video: Gorillas vertical wading and wet-sit-eating

left: dryland gelada, long-tailed, vertical-trunk, dry-sit-eat grasses, no air sac
right: lowland gorilla, tail-less, vertical-trunk, wet-sit-eat sedges, air sac


Another Video: Lowland Gorillas eating sedge rhyzomes and high-protein AHV (Aquatic Herbaceous Vegetation) while sitting-floating in forest open wetland Arkive video link

DD: The question is not "do air sacs always cause loss of tail?", but "is the complete loss of tail in hominoids due (in part) to laryngeal air sac?" The answer is clear, yes, float-sit-feeding with inflatable air sac selects for tail loss.

MV: Not so clear IMO: may depend on body size, size of airsacs, terrestrial vs aquatic milieu, salt vs fresh water milieu, time spent in trees & water, arm-hanging vs hopping vs above-branch, etc.

DD: parallel convergence at forest-waterside (swamp, wetland, shore):

left: Axlotl, long-tailed 'tadpole' with external gills and legs, swims but doesn't sit
right: Macaque, long-tailed, with lungs and legs, swims but doesn't feed sit-floating



Tadpoles with long tail swim, they don't sit partially feeding in water, they don't have prehensile tongue; frogs with no tail sit partially in water, and use long prehensile tongue to eat. Some frogs then evolved more arboreal traits (better climbing skills, less swimming), others spend much time on lake bottoms and developed more aquatic traits (skin 'gill' breathing)

left: tree frogs have since further specialized to arborealty, more 'spidery' and colorful
right: aquatic frog with hydrodynamic red external gills re-adapted to full submersion



Monkeys with long tails swim (Nasalis, Long-tailed macaque); while Ndoki swamp gorillas
(~LCA H-oid) with no tail sit partially in water while feeding.

left: tree apes have since further specialized to arborealty, more 'spidery' and colorful
right: aquatic apes (humans) with hydrodynamic hair re-adapted to submersion diving



AFAIK, neither spidery tree frogs nor deep-submersion frogs inflate their throat air sacs as much as forest-waterside frogs.

AFAIK, neither spidery tree apes (gibbon) nor deep submersion apes (humans) inflate their throat air sacs as much as forest-waterside apes.

Parallel pattern. Partial sit-float eating -> air sac -> tail lost; eventually species body size may enlarge at forest-waterside, OR become full-time spidery at arboreal canopy OR adapt deep submersion with active skin glands* or skin gills* as per photos.

DD: Complete loss of tail = vertical-trunk float-sitting while plucking-foraging. Laryngeal air sacs. Compare to long tailed gelada sitting while plucking-foraging grass on dry ground. No air sacs there, of course.

MV: Some baboons have short tails IIRC?

DD: None lost their tail, many highland monkeys (cold nights select for short tails) with non-prehensile tails have short tails. Tail covers peri-anal region, in water, muscle valves and tissue close peri-anal region.

Dry-sit-eating (no air sac, long-tailed) savanna gelada vs wet/float-sit-eating (air sac, tail-less) Ndoki swamp gorilla
http://tech.groups.yahoo.com/group/AAT/message/49817

* frogs and salamanders may respire via gills, lungs or skin. I conjecture that the eccrine skin glands of humans (inactive in African apes except volar eccrines) function in very limited respiration. link

Evolution Canyon European-African micro-climates in Jordan Rift Valley

Flowering plants & veination 140ma:
http://www.eurekalert.org/pub_releases/2009-12/w-hdf120109.php
The study, by Dr Tim Brodribb and Dr Taylor Field of the University of Tasmania and University of Tennessee, used plant physiology to reveal how flowering plants, including crops, were able to dominate land by evolving more efficient hydraulics, or 'leaf plumbing', to increase rates of photosynthesis.

"Flowering plants are the most abundant and ecologically successful group of plants on earth," said Brodribb. "One reason for this dominance is the relatively high photosynthetic capacity of their leaves, but when and how this increased photosynthetic capacity evolved has been a mystery."

Using measurements of leaf vein density and a linked hydraulic-photosynthesis model, Brodribb and Field reconstructed the evolution of leaf hydraulic capacity in seed plants. Their results revealed that an evolutionary transformation in the plumbing of angiosperm leaves pushed photosynthetic capacity to new heights.

The reason for the success of this evolutionary step is that under relatively low atmospheric C02 conditions, like those existing at present, water transport efficiency and photosynthetic performance are tightly linked. Therefore adaptations that increase water transport will enhance maximum photosynthesis, exerting substantial evolutionary leverage over competing species.

aquatic imagination

More unique pics http://somethinguniqueforall.blogspot.com/

froggy on my bloggy? 2008 Year of the Frog

copied from Tetrapod Zoology blog, better quality photos and descriptions there:
http://scienceblogs.com/tetrapodzoology/2007/12/flying_frogs_and_friends.php

2008 is the year of the frog. Frogs and other amphibians are under stress, they are keystone species in many ecosystems. See how you can help here: tetrapod zoo