Top Tweets for #wingpatterns

5 months ago

On the #mimicry of flies of the genus #Goniurellia (#Tephritinae, #Diptera), whose #wingpatterns make them appear unattractive to #predators. The larger taxon #Tephritidae includes species whose adults possess striking wing patterns, many with abstract appearing "motifs". But they all have functions, mimesis or mimicry. It's about life protection. This is despite the fact that one might think that such special morphologies wouldn't be worthwhile given the very short #lifespan of these adult flies. But #evolution doesn't work that way, because the survival of a species depends on #reproductivesuccess. If females are eaten before laying eggs, they cannot pass on their genetic material to subsequent generations. Furthermore, if, as with these fruit flies, they are in fact #defenseless, the #selectivepressure to develop other kinds of defense mechanisms is very strong. A strategy for protection that has frequently evolved in the animal kingdom is the #imitation of other, more defensive animals. As if an artist had worked on the #wings of the Tephritidae, the patterns can depict complete insects with very impressive precision and #detail. And yet, it is the result of gradual selection and evolution. Ultimately, chance decides. Individuals that, due to #variability, can fend off more predators and therefore survive more often, also reproduce more successfully. Their genetic material is preserved, while that of others dies out. In principle, it is a game of trial and error. With quite striking end results. For example, flies of the genus Goniurellia, which includes about 10 known species, display an impressive pattern on both sides of their wings that is highly detailed and reminiscent of an ant. It has a head, body, six legs, and even something resembling eyes. And yet, this is not a sudden innovation, but the result of gradual evolution. The current appearance of the pattern was essentially determined by the flies' predators. The more the predator could recognize an ant in the originally abstract pattern, the more often the fly was spared from being eaten and was able to reproduce. Goniurellia is a beautiful example of how precisely the #principle of evolution can work Mimicry is often associated with #activebehavior by the animal employing this strategy. The eyespot of the well-known peacock butterfly (Lepidoptera) is particularly effective when the wings are opened abruptly. Flies of the genus Goniurellia also enhance the effect of two defensive and therefore unattractive ants, one per wing, through wing movements that create the illusion that the ants are even moving. When I look at various wing patterns of species from other genera of Tephritidae, I suspect that some of them serve primarily as camouflage (#mimesis), in which the outline of the animal optically dissolves, making it appear to blend into its surroundings. However, I haven't deeper researched whether there are actually theories suggesting that mimicry in these flies evolved from mimesis. The author B. Merz (2002) described three new species of Goniurellia from Soccotra Island (Yemen) and Oman. The ant-like wing #markings of these #species are clearly visible in his drawings (pdf see link). © #StefanFWirth Berlin January 2026 Reference B. Merz (2002) https://t.co/nIyLVhbpYL

Science girl

@sciencegirl

5 months ago

Look at the wings of these flies, from the genus Goniurellia. Each wing has a detailed image of an ant, when the wings move, the ants appear to walk Most of its predators would want to avoid a confrontation with the stings of ants, a body guard “painted” by nature on each side 📸1) mpergil 📸2) Dr Brigitte Howarth