Maahesian Mimicry

Sourial describes an alternative evolutionary pathway from that of Sexual Selection for ornamental plumage in Galliformes. He expands the limitations of animal defense theory by demonstrating multiple applications of display behaviors, postures and quill vibration in the Polyplectroninae: Polyplectron genus, and Pavoninae: Rheinardia, Argusianus, Pavo, and Afropavo genera. The term “Maahesian Mimicry” is used to describe various forms of reptile mimicry employed by Polyplectroninae and Pavoninae in the defense nest sites and foraging territories against reptilian and small mammalian predators. Highly specialized feather quills and ratchis enable the birds to broadcast vibratory signals, unseen to the eavesdropping intruder.
Galliformes generally nest on or near the ground. Their incubation can be quite lengthy, from 21 to 32 days in duration. At this time, the female and her eggs are vulnerable to predation. Monitor lizards, snakes and other reptiles are adept bird predators often specializing on eggs, chicks, juveniles and incubating females. Male Galliformes of the aforementioned genera select nest sites with special environmental features that enable specific forms of nest defense against this class of predators.
The hearing of reptiles varies among the species, but most can hear at least low-pitched sounds. The majority of reptiles have an eardrum, a middle ear, and an inner ear. However, snakes lack a middle ear and cannot hear most sounds carried through the air. Snakes and other reptiles "hear" by sensing vibrations from the ground. Males of these Galliform genera exploit the reptiles' relatively limited auditory capacities by vibrating greatly elongated and highly specialized feather quills behind them as they move rapidly along narrow trails. After the territory defending male Galliform senses that an intruder has entered the nesting territory, it folds its plumage compactly and shuttles rapidly through the vegetation, often utilizing erratic deportment and other diversionary distraction movements.
During these encounters, males hold their special, elongated plumage behind them at specific heights. As they move they spread out their specialized plumage horizontally in such a manner that the train brushes against surrounding vegetation. Some species including the two Great Argus species, stamp their feet loudly, to attract still more attention as they move. Both genera of Argus; Peacock-Pheasants and the Congo Peafowl utilize leaf litter in the diversionary distraction phase of their defensive display behaviors. Some species (genera Rheinardia and Argusianus) laterally compress the plumage in such a manner that the surfaces of the wing and tail closest to the ground are dragged through deep leaf litter. Other species in the genus Polyplectron, laterally compress their entire bodies against the ground, vibrating retrice quills and kicking their feet in specially excavated depressions in the substrate. The Congo Peafowl combines both methods of quill vibration. The larger species use vertical vegetation lining narrow pathways created by the birds to amplify vibrations broadcast by the rapid shivering of plumage quills. Potential nest predators and other intruders utilizing scent, and eavesdropping behaviors to locate nests and potential prey,are sent unambiguous signals from the approaching male Galliform that closely resemble the auditory/vibratory signals of large, predatory reptiles tracking their prey. Or in the case of the diminutive Polyplectron species, the signal may serve as an attractant or lure to larger predatory reptiles and a deterrent to smaller non-obligatory predators like Jungle Squirrels and other deep forest rodents.
The astonishing 'courtship' rituals of these species may in effect be demonstrations of the male's capacity to defend nest sites and progeny against attack. It should be remembered that reptiles cannot digest feathers.
Some deep forest genera, for example, Polyplectron, Rheinardia, and Argusianus, push their plumage downwards in such a manner as to utilize leaf litter to amplify their vibratory signals.
The Galliformes are, in effect, mimicking the auditory and vibratory presence of large predatory reptiles. Many species of the nest predators are small enough to easily become prey themselves. Through vibratory size enhancing behaviors the male Galliform bird deceives the uninitiated nest predator into reacting defensively. They will cease tracking their prey and retreat as if they sense that they are being tracked by larger more dangerous reptilian predator.
This article will be improved on in the future.
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