Unlike the blesbok, the bontebok (Damaliscus pygargus pygargus) lacks an auricular flag

@jwidness @michalsloviak @tonyrebelo @simontonge @jeremygilmore @oviscanadensis_connerties @tandala @colin25 @beartracker @grinnin @botswanabugs @gigilaidler @christiaan_viljoen

Dear Reader, what do you notice about the ears in the following photos?

Blesbok
https://www.inaturalist.org/observations/70348639

Bontebok
https://www.inaturalist.org/observations/115957749

The adaptive colouration of the two subspecies of Damaliscus pygargus is intriguing.

The bontebok (Damaliscus pygargus pygargus) and the blesbok (Damaliscus pygargus phillipsi) are, in most respects, more and less vivid versions of each other.

Therefore, it would have surprised nobody if a conspicuous feature of colouration in the blesbok were even more conspicuous in the bontebok.

Yet, in the case of the auricular flag, the opposite is the case.

In both subspecies, the posterior surface of the ear pinnae is greyish, apparently owing to the dark skin being sparsely covered with short, pale pelage (https://www.dreamstime.com/royalty-free-stock-images-african-bontebok-antelope-image6502609).

Because this pelage has a sheeny quality, the ear pinnae can appear conspicuously pale in certain illuminations.

And this sheeny pallor, although a small feature relative to the size of the whole animal, can serve as a social signal by virtue of the mobility of the ear pinnae.

The following footage of the blesbok is illustrative:

https://stock.adobe.com/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=damaliscus&order=relevance&safe_search=1&limit=100&search_page=16&search_type=pagination&get_facets=0&asset_id=554758522

https://stock.adobe.com/search/images?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=damaliscus&order=relevance&safe_search=1&limit=100&search_page=8&search_type=pagination&get_facets=0&asset_id=542644196

https://stock.adobe.com/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=damaliscus&order=relevance&safe_search=1&limit=100&search_page=16&search_type=pagination&get_facets=0&asset_id=555590119

What is particularly intriguing:

Contrary to expectations, it is the generally duller subspecies, namely the blesbok, that qualifies as possessing an auricular flag, whereas the more vivid subspecies, namely the bontebok, does not.

The failure of the bontebok to qualify for an auricular flag is owing to the following factors:

BLESBOK (see https://www.inaturalist.org/journal/milewski/75748-adaptive-colouration-in-the-blesbok-damaliscus-pygargus-phillipsi#)

The following show the auricular flag in the blesbok:

https://stock.adobe.com/search?k=damaliscus&asset_id=528793101

https://www.dreamstime.com/stock-photo-blesbuck-late-afternoon-field-blesbok-antelope-endemic-to-south-africa-has-distinctive-white-image77761759

https://www.gettyimages.pt/detail/foto/portrait-of-a-blesbok-eating-grass-imagem-royalty-free/71104635?adppopup=true

https://www.robertharding.com/preview/764-6027/blesbok-damaliscus-pygargus-phillipsi-male-chasing-mountain-zebra/

https://www.gettyimages.pt/detail/fotografia-de-not%C3%ADcias/blesbok-in-the-bioparc-valencia-november-07th-fotografia-de-not%C3%ADcias/1440188664?adppopup=true

Third photo in https://www.inaturalist.org/observations/141372682

Second photo in https://www.inaturalist.org/observations/41711968

https://www.inaturalist.org/observations/146961908

https://www.inaturalist.org/observations/107178201

Scroll to second photo in http://cameratrap.mywild.co.za/2012/02/more-herbivores-at-suikerbosrand.html

https://stock.adobe.com/search?k=damaliscus&asset_id=574779666

https://stock.adobe.com/search/images?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=damaliscus&order=relevance&safe_search=1&limit=100&search_page=3&search_type=pagination&get_facets=0&asset_id=441942924

https://stock.adobe.com/search?k=damaliscus&asset_id=32501730

https://stock.adobe.com/search/images?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=damaliscus&order=relevance&safe_search=1&limit=100&search_page=2&get_facets=0&search_type=pagination&asset_id=447452844

https://upload.wikimedia.org/wikipedia/commons/2/22/Damalicus_pygargus_phillipsi_Dvur_zoo_2.jpg

https://www.inaturalist.org/observations/32226381

https://www.stockfreeimages.com/388844/Blesbok.html

https://upload.wikimedia.org/wikipedia/commons/1/13/Barcelona-Zoo-Damalisco_de_frente_blanca_%28Damaliscus_dorcas_phillipsi%29_%28I%29.jpg

https://www.gettyimages.pt/detail/foto/blesboks-running-imagem-royalty-free/90498079?adppopup=true

https://stock.adobe.com/search/images?filters%5Bcontent_type%3Aphoto%5D=1&filters%5Bcontent_type%3Aillustration%5D=1&filters%5Bcontent_type%3Azip_vector%5D=1&filters%5Bcontent_type%3Avideo%5D=0&filters%5Bcontent_type%3Atemplate%5D=0&filters%5Bcontent_type%3A3d%5D=0&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=blesbok&order=relevance&price%5B%24%5D=1&safe_search=1&search_page=2&get_facets=0&search_type=pagination&asset_id=544432988

Third photo in https://www.inaturalist.org/observations/10869372

https://www.inaturalist.org/observations/10805336

https://www.gettyimages.pt/detail/foto/blesbok-antelopes-in-swaziland-imagem-royalty-free/92951908?adppopup=true

https://www.euro-t-guide.com/See_Photo/Denmark/JUT-M_Grenaa/Ree_Park_Ebeltoft-2008-14.jpg

https://depositphotos.com/635653818/stock-photo-blesbok-blesbuck-damaliscus-pygargus-phillipsi.html

https://www.inaturalist.org/observations/56204460

https://de.wikipedia.org/wiki/Buntbock#/media/Datei:Damaliscus_pygargus_-_R%C3%A9serve_africaine_de_Sigean_02.jpg

Scroll to seventh photo in https://www.dailymaverick.co.za/article/2022-12-07-mountain-zebra-national-park-back-from-the-brink/

https://www.inaturalist.org/observations/147672580

https://www.mindenpictures.com/stock-photo-blesbok-damaliscus-dorcas-phillipsi-adult-female-with-calf-malolotja-naturephotography-image80144737.html

https://www.inaturalist.org/observations/108296682

https://www.istockphoto.com/photo/african-blesbok-antelope-gm541305272-96817503

https://www.istockphoto.com/photo/two-beautiful-blesboks-gm1388891630-446375145?phrase=blesbok%20male

https://www.shutterstock.com/it/image-photo/blesbok-blesbuck-damaliscus-dorcas-phillipsi-497011039

https://stock.adobe.com/search/images?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=damaliscus&order=relevance&safe_search=1&limit=100&search_page=8&search_type=pagination&get_facets=0&asset_id=252055834

https://stock.adobe.com/search/images?k=blesbock&asset_id=32186683

BONTEBOK

The following show that, in the bontebok, there is a hint of the same pattern.

https://upload.wikimedia.org/wikipedia/commons/f/f8/Bontebok_PA020073.JPG

https://www.inaturalist.org/observations/84604329

https://www.gettyimages.pt/detail/foto/oryx-imagem-royalty-free/974402214?adppopup=true

https://www.shutterstock.com/it/image-photo/endangered-bontebok-antelope-damaliscus-pygargus-dorcas-572224153

Scroll to sixth photo in https://www.melozhori.co.za/fun-facts-about-bontebok/

Second photo inhttps://www.inaturalist.org/observations/63340921

https://stock.adobe.com/search?k=damaliscus&asset_id=437876858

https://www.inaturalist.org/observations/99715628

Third photo in https://www.inaturalist.org/observations/104349170

https://www.inaturalist.org/observations/71049460

https://stock.adobe.com/search/images?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=damaliscus&order=relevance&safe_search=1&limit=100&search_page=3&search_type=pagination&get_facets=0&asset_id=221437252

https://fototravel.net/licencias/damaliscus-dorcas-dorcas-sudafrica/

https://stock.adobe.com/search/images?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=damaliscus&order=relevance&safe_search=1&limit=100&search_page=7&search_type=pagination&get_facets=0&asset_id=271748452

https://www.inaturalist.org/observations/114683864

Scroll to third photo in https://www.goodthingsguy.com/environment/the-bontebok-brought-back-from-the-edge-of-extinction/

https://www.inaturalist.org/observations/128976508

https://www.inaturalist.org/observations/115214084

https://depositphotos.com/240206084/stock-photo-bontebok-antelope-southern-african-savanna.html

https://www.inaturalist.org/observations/136011434

https://www.inaturalist.org/observations/115175564

Scroll to second photo in https://www.monaconatureencyclopedia.com/damaliscus-dorcas/?lang=en

https://www.inaturalist.org/observations/97174996

https://www.inaturalist.org/observations/59053711

https://www.inaturalist.org/observations/75893694

https://www.inaturalist.org/observations/115550547

https://www.inaturalist.org/observations/39079379

https://www.inaturalist.org/observations/22321093

https://www.inaturalist.org/observations/27817980

https://www.inaturalist.org/observations/34601885

https://www.inaturalist.org/observations/31418950

https://www.inaturalist.org/observations/63459199

https://www.inaturalist.org/observations/24374180

https://www.inaturalist.org/observations/23198842

https://www.inaturalist.org/observations/10796733

https://www.inaturalist.org/observations/11166243

https://www.inaturalist.org/observations/45157961

https://www.inaturalist.org/observations/80650367

https://www.inaturalist.org/observations/61544194

https://www.inaturalist.org/observations/70047849

https://www.inaturalist.org/observations/69368070

https://www.inaturalist.org/observations/99626194

The following of the bontebok nearly qualify as showing an auricular flag:

https://stock.adobe.com/search/images?k=blesbock&asset_id=432947109.

https://www.inaturalist.org/observations/148322103

DISCUSSION

The comparison can be summarised by means of the following photo-pair.

Blesbok
https://www.inaturalist.org/observations/32226381

Bontebok
https://www.inaturalist.org/observations/30830045

Were it the case that the bontebok was the sole form of Damaliscus pygargus, probably nobody would have noticed the colouration of its ear pinnae, at all.

However, the noticeable 'flashing' of the ears in the blesbok has set up a search-image. According to the standard set by the blesbok, the bontebok falls short.

There are thousands of photos of the bontebok on the Web, but few come close to showing the clarity and consistency of the auricular flag seen in this view of the blesbok: https://stock.adobe.com/search/images?filters%5Bcontent_type%3Aphoto%5D=1&filters%5Bcontent_type%3Aillustration%5D=1&filters%5Bcontent_type%3Azip_vector%5D=1&filters%5Bcontent_type%3Avideo%5D=0&filters%5Bcontent_type%3Atemplate%5D=0&filters%5Bcontent_type%3A3d%5D=0&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=blesbock&order=relevance&price%5B%24%5D=1&safe_search=1&limit=100&search_page=2&get_facets=0&search_type=pagination&asset_id=142342741.

The following pair of photos of the blesbok shows the full difference produced by angle of illumination, via the sheeny quality of the pelage on the posterior surface of the ear pinna:

https://stock.adobe.com/search/images?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=damaliscus&order=relevance&safe_search=1&limit=100&search_page=8&search_type=pagination&get_facets=0&asset_id=362066099 versus https://stock.adobe.com/search/images?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=damaliscus&order=relevance&safe_search=1&limit=100&search_page=8&search_type=pagination&get_facets=0&asset_id=256689589

The following shows the difference, within a single specimen (https://stock.adobe.com/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=damaliscus&order=relevance&safe_search=1&search_page=9&get_facets=0&search_type=pagination&asset_id=10848983).

A possible explanation for the lack of an auricular flag in the bontebok is that the behaviours of the two subspecies differ.

The blesbok habitually head-nods (https://stock.adobe.com/search/images?filters%5Bcontent_type%3Aphoto%5D=1&filters%5Bcontent_type%3Aillustration%5D=1&filters%5Bcontent_type%3Azip_vector%5D=1&filters%5Bcontent_type%3Avideo%5D=0&filters%5Bcontent_type%3Atemplate%5D=0&filters%5Bcontent_type%3A3d%5D=0&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=blesbock&order=relevance&price%5B%24%5D=1&safe_search=1&limit=100&search_page=5&search_type=pagination&get_facets=0&asset_id=415281887 and https://stock.adobe.com/search/images?filters%5Bcontent_type%3Aphoto%5D=1&filters%5Bcontent_type%3Aillustration%5D=1&filters%5Bcontent_type%3Azip_vector%5D=1&filters%5Bcontent_type%3Avideo%5D=0&filters%5Bcontent_type%3Atemplate%5D=0&filters%5Bcontent_type%3A3d%5D=0&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=blesbock&order=relevance&price%5B%24%5D=1&safe_search=1&limit=100&search_page=5&search_type=pagination&get_facets=0&asset_id=415281850 and https://stock.adobe.com/search/images?filters%5Bcontent_type%3Aphoto%5D=1&filters%5Bcontent_type%3Aillustration%5D=1&filters%5Bcontent_type%3Azip_vector%5D=1&filters%5Bcontent_type%3Avideo%5D=0&filters%5Bcontent_type%3Atemplate%5D=0&filters%5Bcontent_type%3A3d%5D=0&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=blesbock&order=relevance&price%5B%24%5D=1&safe_search=1&limit=100&search_page=7&search_type=pagination&get_facets=0&asset_id=415281880).

It does this to an extent and with a frequency that I have not noticed in the bontebok.

Head-nodding, as well as standing in the midday sun with the head lowered and the ears drooping, would tend to display the auricular flag (https://depositphotos.com/154297952/stock-video-blesbok-antelopes-in-grassland.html and https://www.dreamstime.com/stock-photo-cattle-bontebok-antelopes-south-africa-safari-tala-game-reserve-image45175407 and https://stock.adobe.com/search/images?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=damaliscus&order=relevance&safe_search=1&limit=100&search_page=8&search_type=pagination&get_facets=0&asset_id=566483214).

For an index to my many Posts about the genus Damaliscus, please see https://www.inaturalist.org/journal/milewski/78238-an-index-to-my-posts-on-genus-damaliscus#.

Publicado el marzo 2, 2023 06:18 TARDE por milewski milewski

Comentarios

If known, in the event that the Blesbok and Bontebok (Damaliscus pygargus ssp.) hybridise, which flags could they possibly possess?

Publicado por paradoxornithidae hace 12 meses

@paradoxornithidae

The following is my best guess, for now.
The difference between bleeze and flag,is that the former is prominent enough to be conspicuous even at a distance and even when the figure is stationary, whereas the latter becomes conspicuous only with movement.

Bearing this in mind, the two subspecies differ as follows.

BLESBOK

Bleezes: only facial

Flags: auricular, pygal, ulnar, abdominal, and pedal

BONTEBOK

Bleezes: facial, pygal, and lateral (the latter subsuming the ulnar pattern)

Flags: pedal (better-developed than the pedal flag of the blesbok, but not qualifying as a bleeze because the whitish is too low on the figure)

HYBRIDS

This depends on which of the two phenotypes tends to be 'dominant' in hybridisation. I suspect that the answer is that the phenotype of the blesbok tends to be dominant (please see https://www.inaturalist.org/observations/10956454).

If so:

Bleezes: facial in all individuals, with some individuals retaining the pygal bleeze of the bontebok

Flags: pygal, ulnar, abdominal, and pedal (but not auricular)

Publicado por milewski hace 12 meses

Mokala was acquired by SANParks as an inappropriately stocked game farm. Lots of rubbish in it!

Publicado por tonyrebelo hace 12 meses

Let us assume that the ear pinnae are the same size in the blesbok and the bontebok.

If the face of the blesbok is relatively large, but the ear pinnae are the same size in blesbok vs bontebok, then close-up, full-frontal photos should show different lengths of the white rostral patch relative to the ear pinna.

I performed a preliminary test of this, on the basis of photos on the Web.

I found that the white rostral patch (measured from the edge of the rhinarium) is 146% of the ear pinna (measured from the meatus, not the base of the ear) in the blesbok, vs 130% in the bontebok.

This leads me to suggest the following:
A distinction between the blesbok and the bontebok is that the facial bleeze is more than 1.4-fold longer than the ear pinna in the former, vs less than 1.4-fold in the latter.

Blesbok

https://www.flickr.com/photos/88098601@N05/9061853401/

https://www.istockphoto.com/photo/wild-male-african-antelope-blesbok-looks-at-the-camera-gm1223280959-359281865?phrase=bontebok

https://www.istockphoto.com/photo/wild-african-animals-bontebok-is-one-of-the-rarest-antelope-in-the-world-on-the-gm1227498213-362043636?phrase=bontebok

https://www.alamy.com/stock-photo-bontebok-83504695.html?imageid=3DD3BCD3-CAD5-483C-BB1C-49A8C2F8AF01&p=86438&pn=1&searchId=798d07205e132c3bcbdbb01855d0a786&searchtype=0

https://www.istockphoto.com/photo/wild-african-animals-bontebok-is-one-of-the-rarest-antelope-in-the-world-on-the-gm1247754738-363380990

Bontebok

https://www.alamy.com/bontebok-portrait-image600041.html?imageid=CCAF0231-8FCA-4657-B866-5594A6B88FC4&p=4877&pn=1&searchId=798d07205e132c3bcbdbb01855d0a786&searchtype=0

https://www.alamy.com/stock-photo-bontebok-blesbok-damaliscus-dorcas-portrait-in-flowering-meadow-south-17800012.html?imageid=04D80201-DB01-4413-A3D2-680B2DC4661B&p=33533&pn=1&searchId=8e0e27dee5438b0aebbf70d1e52c6061&searchtype=0

https://www.alamy.com/stock-photo-bontebok-damaliscus-pygargus-buck-overberg-south-africa-125626543.html?imageid=22F225B8-915A-4DD3-A54D-5338CF6317B4&p=361347&pn=1&searchId=8e0e27dee5438b0aebbf70d1e52c6061&searchtype=0

https://www.shutterstock.com/it/image-photo/bontebok-antelope-de-hoop-nature-reserve-126157499

https://www.pexels.com/photo/selective-focus-photography-of-springbok-2078470/

Publicado por milewski hace 12 meses

The following are some of the few photos on the Web that
suggest an auricular flag in the bontebok. However, they are too few to be typical:

https://www.inaturalist.org/observations/26539954

https://www.inaturalist.org/observations/148322103

Publicado por milewski hace 12 meses

One of the clues to these three photos (https://www.inaturalist.org/observations/45807072 and https://www.inaturalist.org/observations/45807069) being of hybrids, as opposed to the bontebok, is the conspicuousness of the auricular flag in two of the figures. Indeed, this is one of the best illustrations on the Web of the sheeny gleam of the auricular flag of Damaliscus pygargus.

Publicado por milewski hace 12 meses

Another clear illustration of auricular flag in Damaliscus pygargus phillipsi:

https://www.inaturalist.org/observations/185403305

Publicado por milewski hace 5 meses

@matthewinabinett @paradoxornithidae

The following, of Damaliscus pygargus phillipsi in the rain, supports my assumption that the auricular flag depends partly on sheen (as opposed to depigmentation alone). Without direct sunlight, and with a wet surface, the pelage on the posterior surface of the ear pinna does not appear strikingly pale. By the same token, the ulnar flag is as prominent as in sunny conditions, indicating that this feature does not depend on any sheen effect:

https://www.inaturalist.org/observations/190321352

Also see https://www.inaturalist.org/observations/192711642

Publicado por milewski hace 4 meses
Publicado por milewski hace alrededor de 2 meses
Publicado por milewski hace alrededor de 2 meses
Publicado por milewski hace alrededor de 1 mes

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