'Hyperconspicuousness', in terms of adaptive colouration in ungulates, is defined by bold colouration in adults of both sexes, at all seasons, and also in infants.
It is in the conspicuousness of infants that the concept of 'hyper' arises, because it would be expected that this stage of growth, particularly vulnerable to predation, would not be exposed in the same way as the juvenile to mature stages.
I have previously described the takhi (Equus przewalskii) as hyperconspicuous (https://www.inaturalist.org/journal/milewski/66546-a-hyperconspicuous-horse-hiding-in-plain-sight#).
This is based on patterns so bold that the whole figure is conspicuous even when stationary, in both
I have also pointed out that a prime example of hyperconspicuous colouration, among ruminants, is Connochaetes mearnsi.
In my recent scrutiny of the red hartebeest (Alcelaphus caama), it has dawned on me that this species may possibly also qualify as possessing hyperconspicuous colouration (https://stock.adobe.com/au/search?filters%5Bcontent_type%3Aphoto%5D=1&filters%5Bcontent_type%3Aillustration%5D=1&filters%5Bcontent_type%3Azip_vector%5D=1&filters%5Bcontent_type%3Avideo%5D=1&filters%5Bcontent_type%3Atemplate%5D=1&filters%5Bcontent_type%3A3d%5D=1&filters%5Bcontent_type%3Aaudio%5D=0&filters%5Binclude_stock_enterprise%5D=0&filters%5Bis_editorial%5D=0&filters%5Bfree_collection%5D=0&filters%5Bcontent_type%3Aimage%5D=1&k=%22red+hartebeest%22&order=relevance&safe_search=1&limit=100&search_page=12&search_type=pagination&get_facets=0&asset_id=414565863).
The reasons why I have been slow to realise this include:
I can now make the following case, by means of comparative illustrations with the takhi.
The colouration of adults in Alcelaphus caama is conspicuous, even when stationary, owing to a combination of
Infants emerge from hiding at only two weeks old, when their colouration is still distinctively pale, accentuated by a precocially dark tail.
Furthermore, the rest of the bleeze on the hindquarters is also noteworthy in its precociality, starting to develop before the ground-colour darkens to the medium tone seen in adults. Indeed, in at least some individual infants, the bleeze starts to appear before the umbilical cord disappears (https://www.shutterstock.com/image-photo/newborn-red-hartebeest-looking-over-his-510145570).
In adults of the takhi, there is no particular bleeze. However, there is dark/pale contrast among the lower legs, tail, mane, and nose (all dark), and flanks, buttocks, and muzzle (all pale) - which combine to make the figure conspicuous as a whole, from all perspectives:
https://www.inaturalist.org/observations/71816485
https://www.flickr.com/photos/danielahartmann/10175540443
https://www.naturalhistoryonthenet.com/Mammals/PrzewalskisHorse.htm
https://www.shutterstock.com/image-photo/przewalskis-horse-equus-ferus-przewalskii-known-1257519664
https://www.globetrotting.com.au/horse-breed-przewalskis-horse/
In adults of the red hartebeest, there is a particular bleeze (consistent among individuals), consisting of
This bleeze is absent in newborns, and is somewhat 'dimmed' in mature males.
The following shows that the bleeze starts to develop in the infant: https://www.masterfile.com/image/en/6119-08242958/red-hartebeest-alcelaphus-buselaphus-calf-karoo-national.
https://www.shutterstock.com/image-photo/red-hartebeest-herd-kgalagadi-transfrontier-park-223525426
https://www.shutterstock.com/image-photo/red-hartebeest-bush-etosha-nationparc-namibia-2168682787
In fully mature males, the pale of the bleeze tends to darken, but overall conspicuousness tends to be maintained by the degree of overall darkness (https://stock.adobe.com/au/search?filters%5Bcontent_type%3Aphoto%5D=1&filters%5Bcontent_type%3Aillustration%5D=1&filters%5Bcontent_type%3Azip_vector%5D=1&filters%5Bcontent_type%3Avideo%5D=1&filters%5Bcontent_type%3Atemplate%5D=1&filters%5Bcontent_type%3A3d%5D=1&filters%5Bcontent_type%3Aaudio%5D=0&filters%5Binclude_stock_enterprise%5D=0&filters%5Bis_editorial%5D=0&filters%5Bfree_collection%5D=0&filters%5Bcontent_type%3Aimage%5D=1&k=%22red+hartebeest%22&order=relevance&safe_search=1&limit=100&search_page=12&search_type=pagination&get_facets=0&asset_id=257384153 and https://www.shutterstock.com/image-photo/red-hartebeest-kgalagadi-south-africa-2160034269 and https://realorasafaris.co.za/product/red-hartebeest/ and https://www.posterazzi.com/red-hartebeest-etosha-national-park-namibia-africa-poster-print-by-jaynes-gallery-item-varpddaf31bja0119/ and https://fineartamerica.com/featured/red-hartebeest-belinda-greb.html).
Whether Alcelaphus caama qualifies as hyperconspicuous, or not, may depend on three main questions, viz.
Skinner and Smithers (2005), citing Kok (1975), state: "mothers recognise their calves at distances up to 300 m and if the herd takes flight the calves rejoin therir mothers in flight...calves that are unable to keep up with the herd fall flat on the ground and lie still, as an avoidance reaction to following predators."
Infants are pale in human eyes, but clearly not pale enough to negate their tactic of hiding under some circumstances. Therefore, the question that seems crucial is whether, infants have any features conspicuous to the eyes of ungulates, in ultraviolet, that tend to be obscured when the figure lies flat on the ground.
Mature males, in their prime, seem to become dark enough to remain conspicuous, despite the loss of some of the conspicuous paleness of the bleeze (see https://www.inaturalist.org/journal/milewski/71379-the-red-hartebeest-shows-subtle-convergence-with-a-coexisting-giraffe-in-darkening-for-masculine-conspicuousness#).
Alcelaphus cokii seems to differ from A. caama in that infants do not differ much from their mothers in the ground-colour (https://www.bigstockphoto.com/image-366065119/stock-photo-young-hartebeest-leaves-mother-in-sunlit-savannah).
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https://www.globaltimes.cn/page/202110/1236364.shtml
https://www.treehugger.com/przewalskis-horse-things-you-didnt-know-about-the-last-wild-horses-4863638
https://www.youtube.com/watch?v=VyweNYH8CO8
https://nationalzoo.si.edu/animals/news/new-zoo-przewalskis-horses
http://www.xinhuanet.com/english/2019-05/24/c_138085906_3.htm
https://somethingovertea.wordpress.com/2020/01/26/the-lovely-red-hartebeest/
https://www.shutterstock.com/image-photo/red-hartebeest-alcelaphus-buselaphus-rainy-season-1554828335
https://www.shutterstock.com/image-photo/red-hartebeest-dry-heat-etosha-wildlife-722690560
https://www.shutterstock.com/image-photo/cokes-hartebeest-alcelaphus-buselaphus-cokii-kongoni-88482637
The sheen/gloss on the pelage of Alcelaphus caama is potentially capable of making the figure somewhat conspicuous even when viewed from the front.
Skinner and Chimimba (2005) state: "The forehead is black...and a black band on top of the muzzle. These and the other black markings on the body have an iridescence that in some lights gives them a plum-coloured sheen. In strong light the iridescence is so pronounced that, when the individual is standing facing the observer, the black on the forehead and muzzle shines white and has thus given rise to the widely current belief...that some individuals have white face blazes."
The following specimen (https://www.inaturalist.org/observations/10857932) seems to show depigmented hairs, rather than sheen/gloss.
The following suggests that, at least in certain illuminations, there is a conspicuous contrast between the far forehead and the pale anterior surface of the ear pinnae:
https://www.inaturalist.org/observations/37160566
The following show the conspicuous effect of sheen on the flanks:
https://www.inaturalist.org/observations/25551798
https://www.inaturalist.org/observations/10801899
https://depositphotos.com/366432062/stock-photo-herd-red-hartebeest-bucks-attentive.html
The following show that the ground-colour of infants is paler than that of adult females, in Alcelaphus caama:
https://www.imago-images.com/st/0150537360
https://www.shutterstock.com/video/clip-5584211-red-hartebeest-antelope-alcelaphus-buselaphus-suckling-calf
The following show that the ground-colour of infants is similar to that of adult females, in Alcelaphus cokii:
https://www.shutterstock.com/image-photo/young-hartebeest-approaches-mother-sunlit-savannah-1730346109
https://www.alamy.com/stock-photo-mother-and-baby-hartebeest-alcelaphus-buselaphus-cokes-race-standing-41586065.html
https://www.mindenpictures.com/stock-photo-coke-s-hartebeest-alcelaphus-buselaphus-cokii-mother-and-baby-masai-naturephotography-image00784060.html
Scroll for good photo of hyperconspicuous infant of C. albojubatus:
https://www.zoonewengland.org/franklin-park-zoo/our-animals/mammals/hoofed/white-bearded-wildebeest/
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