In terms of adaptive colouration, a flag is a feature too small to advertise the stationary figure at distance, but presenting enough dark/pale contrast to draw attention to the animal when it moves.
Flags are biologically significant because many animals rely on a combination of concealment and advertisement. Concealment is mainly an anti-predator strategy. Advertisement is used sexually and socially, and in certain species is also part of an anti-predator strategy.
A caudal flag, by definition, refers to the tail (https://www.etymonline.com/word/caudal#:~:text=caudal%20(adj.),%2B%20%2Dal%20(1).), in some cases including the surfaces immediately adjacent to the tail.
The colouration of the tail in the sable antelope (Hippotragus niger) makes this a candidate for a caudal flag.
This is because the tail is
However, there are several aspects detracting from the conspicuousness of the colouration of the tail in the sable antelope, and potentially disqualifying a caudal flag in this species.
These are
The strongest case for a caudal flag can be made for the northernmost subspecies, Hippotragus niger roosevelti, in which the black tail is particularly conspicuous in
adult females (https://www.alamy.com/stock-photo-adult-female-sable-antelope-in-the-shimba-hills-reserve-mombasa-kenya-18915351.html?imageid=5C4C9114-950C-4BF5-8425-0A82973B5A66&p=30436&pn=1&searchId=5025017ea04e94a5648cb5917feeee17&searchtype=0
and https://www.alamy.com/stock-photo-adult-female-sable-antelope-in-the-shimba-hills-reserve-mombasa-kenya-18911904.html?imageid=5C4DFE87-6C61-4D60-AF31-5FA518E724ED&p=30436&pn=1&searchId=5025017ea04e94a5648cb5917feeee17&searchtype=0 and https://www.alamy.com/stock-photo-adult-female-sable-antelope-in-the-shimba-hills-reserve-mombasa-kenya-18913775.html?imageid=D9A707E6-7779-4CC7-9457-39331867AC7A&p=30436&pn=1&searchId=2e077309e440b9a2a7ef0d733bc60ae5&searchtype=0 and https://www.alamy.com/stock-photo-adult-female-sable-antelope-in-the-shimba-hills-reserve-mombasa-kenya-18914863.html?imageid=CEA4B7CF-1416-4899-8988-F73F344DD50E&p=30436&pn=1&searchId=5025017ea04e94a5648cb5917feeee17&searchtype=0 and https://www.inaturalist.org/observations/10735658 and https://www.alamy.com/stock-photo-sable-antelope-hippotragus-niger-female-group-kenya-shimba-hills-national-47887495.html?imageid=CD167EAE-63ED-4D8B-AFA7-645C1FA634F0&p=33612&pn=1&searchId=2e077309e440b9a2a7ef0d733bc60ae5&searchtype=0 and https://www.alamy.com/sable-antelope-hippotragus-niger-shimba-hills-national-park-near-mombasa-image3650566.html?imageid=6B07D979-33BA-41B5-83C2-9A1519F36EDA&p=11788&pn=1&searchId=2e077309e440b9a2a7ef0d733bc60ae5&searchtype=0 and http://lukemberman.blogspot.com/2014/08/the-rare-sable-of-shimba.html and https://www.saga-photography.de/indexcknsh.php?lan=en and https://eol.org/pages/331077/media and https://www.inaturalist.org/observations/106267194 and https://www.alamy.com/stock-photo-adult-female-sable-antelope-in-the-shimba-hills-reserve-mombasa-kenya-18911692.html?imageid=BB9A5394-F007-4212-82BE-CC43A1025C5B&p=30436&pn=1&searchId=2e077309e440b9a2a7ef0d733bc60ae5&searchtype=0 and https://www.alamy.com/stock-photo-sable-antelope-hippotragus-niger-shimba-hills-national-reserve-kenya-27972834.html?imageid=99099299-4DBD-441C-A944-5E50457D88E4&p=18649&pn=2&searchId=d6f6fabe7a39828b69b031e53b4f5258&searchtype=0), and
The sable antelope sometimes raises the tail towards the horizontal while fleeing. However, this seems to be mainly during initial acceleration, being otherwise done in a loose/erratic/non-stereotyped way (https://www.mindenpictures.com/stock-photo-sable-antelope-hippotragus-niger-buck-fleeing-the-river-bank-chobe-naturephotography-image00548856.html and https://www.youtube.com/watch?v=g0u0TbaAY7A and https://www.alamy.com/stock-photo-sable-antelopes-hippotragus-niger-bovidae-at-full-gallop-in-mopane-36820723.html?imageid=501E220A-5A08-4F53-AFB3-D6BB8482AB1F&p=26096&pn=1&searchId=0e6e39bb562061c5ecf0ff4fe4026297&searchtype=0 and https://howieswildlifeimages.files.wordpress.com/2017/03/20151014-d4s_4575.jpg).
However, anti-predator flagging of the tail is shown in the following footage:
Estes (1991, pages 125-127) mentions the following displays of the tail:
Skinner and Chimimba (2005, page 664) state:
"Territorial defence...displays...lateral presentation of the body to the trespasser, the tail held out stiffly and twitching, as the two [mature male rivals] stand near to tail."
DISCUSSION
The sable antelope certainly does display its tail to some extent, both in sexual and social contexts and in anti-predator defence.
It may not be particularly significant that the tail is raised as a sign of dominance/confidence/assertiveness, in intraspecific interactions. This is because such displays are widespread among ungulates and carnivores.
On balance, does the sable antelope does not possess a caudal flag?
I am unsure, but an argument can be made that the colouration of the tail in this species be regarded more as part of the ischio-abdominal bleeze.
Compare, for example, the sable antelope with the red hartebeest (Alcelaphus caama).
Both species possess
Consequently, in both species an argument can be made for a bleeze on the hindquarters.
However, there is a difference in emphasis.
In the sable antelope, the main elements of conspicuousness are the white abdomen and buttocks, to which the tail seems accessory. By contrast, in the red hartebeest the tail is arguably the crucial element of conspicuousness (https://somethingovertea.files.wordpress.com/2020/01/addoredhartebeest4.jpg).
This is partly because the tassel is larger (https://www.wildwbsafaris.com/p25/species-list/red-hartebeest-in-south-africa.html and https://www.stuporterphotography.com/image/I0000zJVlHwxOnLE) in the red hartebeest than in the sable antelope.
Furthermore, the raising of the tail while running is
Both species style-trot, but only the red hartebeest raises the tail during this display (https://pixels.com/featured/red-hartebeest-running-robert-goodell.html and https://www.dreamstime.com/stock-photo-red-hartebeest-wildlife-background-running-dust-gallops-faded-sunset-light-as-seen-wilds-africa-dusk-image41321838 and https://m.facebook.com/kifaruluxurylodge/photos/pcb.1016673712307255/1016673658973927/?type=3&source=48&).
Also, the darkness of the tail is more precocial in the red hartebeest (https://www.alamy.com/stock-photo-red-hartebeest-alcelaphus-buselaphus-caama-calf-standing-kalahari-96170557.html?imageid=C3A5938E-50E3-4E2B-89C7-C0C178EDD2FB&p=11592&pn=1&searchId=6cb6d804e8c2d0cca41f0eed698c3a54&searchtype=0 and https://www.dreamstime.com/stock-image-baby-red-hartebeest-antelope-image13753251) than in the sable antelope (https://www.alamy.com/sable-antelope-hippotragus-niger-family-two-parents-with-calf-chobe-national-park-botswana-image550660749.html?imageid=C7F2AB70-FBB3-4BAF-8580-10A8D6DA953B&p=2164234&pn=1&searchId=70d6cc7e51432aae845f0cf4336901c8&searchtype=0 and https://www.alamy.com/in-this-june-20-2018-photo-a-baby-sable-antelope-born-may-13-nuzzles-his-mother-at-the-audubon-species-survival-center-in-new-orleans-about-a-year-after-moving-into-spacious-new-digs-in-new-orleans-african-animals-are-doing-just-what-officials-from-two-zoos-had-hoped-being-fruitful-and-multiplying-ap-photogerald-herbert-image511985143.html).
As a result, I would argue that
In the case of females of H. niger roosevelti:
My interpretation is that, in the absence of darkness on the rump, haunches, and upper hindlegs, the tail is the most important element in the ischio-abdominal bleeze (http://www.wild-about-you.com/GameEastAfricanSable.htm and https://www.wildlifeofkenya.com/categories/ongulates/antelope-sable/ and https://www.alamy.com/stock-photo-adult-female-sable-antelope-in-the-shimba-hills-reserve-mombasa-kenya-18912923.html?imageid=96807F0A-EBB3-41F0-8578-4D5BBF1428DB&p=30436&pn=1&searchId=5025017ea04e94a5648cb5917feeee17&searchtype=0 and https://www.alamy.com/roosevelts-sable-image356968100.html?imageid=08F419C3-5193-455E-872A-53BAAAAB6F29&p=557829&pn=1&searchId=5025017ea04e94a5648cb5917feeee17&searchtype=0 and https://www.alamy.com/sable-antelope-hippotragus-niger-in-the-grassy-savannah-of-shimba-hills-national-park-kenya-image233626771.html?imageid=68D04909-9A31-4BE8-9D45-5B22E243FE3A&p=785530&pn=1&searchId=5025017ea04e94a5648cb5917feeee17&searchtype=0 and https://www.alamy.com/stock-photo-adult-female-sable-antelope-in-the-shimba-hills-reserve-mombasa-kenya-18911692.html?imageid=BB9A5394-F007-4212-82BE-CC43A1025C5B&p=30436&pn=1&searchId=5025017ea04e94a5648cb5917feeee17&searchtype=0 and https://www.alamy.com/stock-photo-sable-antelope-hippotragus-niger-roosevelti-shimba-hills-national-31135025.html?imageid=77492FE9-AB45-46AE-9209-A7B55BA5735F&p=74587&pn=1&searchId=5025017ea04e94a5648cb5917feeee17&searchtype=0).
AUDITORY INSTEAD OF VISUAL SIGNALLING?
One adaptive interpretation of the lack of caudal flags in Hippotragus is as follows.
The sable antelope and the roan antelope (Hippotragus equinus) are unusually vocal for antelopes. In the case of the former species, Estes (1991, pages 125-127) mentions that
Also see in https://www.inaturalist.org/journal/milewski/86153-most-ungulates-are-surprisingly-inept-at-using-their-horns-against-predators-part-2-is-the-sable-antelope-hippotragus-niger-really-an-exception#, under the heading ADDITIONAL NOTES.
I therefore suggest that vocalisation is, in part, an auditory substitute for caudal flagging in Hippotragus.
However, this applies only to sexual and social functions of flagging, excluding anti-predator contexts. Hippotragus (and hippotragins generally) seems to lack the caudal flagging seen in various other ungulates as they interact with predators.
Comments
Mature female of Hippotragus niger niger:
https://www.alamy.com/stock-photo-giant-sable-antelope-hippotragus-niger-crossing-red-sand-path-waterberg-90827229.html?imageid=E35CBBD1-500E-46BB-BCD9-937B28C80B30&p=2206959&pn=1&searchId=0452b29cb4460d2129648a818706996d&searchtype=0
Scroll to 8th photo in http://elelur.com/mammals/sable-antelope.html#photo_8 for fully mature male Hippotragus niger niger, clearly showing the size and shape of the tail.
https://www.youtube.com/watch?v=KLYDADGs0VI
https://www.tandfonline.com/doi/pdf/10.1080/00445096.1965.11447324
@paradoxornithidae
HIPPOTRAGUS NIGER VARIANI
https://link.springer.com/chapter/10.1007/978-3-030-03083-4_17
https://africanhuntinggazette.com/giant-sable-conservation-in-angola/
Valuable photo of Alcelaphus cokii:
https://www.alamy.com/cokes-hartebeest-alcelaphus-bucephalus-cokii-mother-and-young-masai-mara-game-reserve-kenya-image262961718.html?imageid=AB2B3BD6-2B1C-4A59-B45C-A24DEEAA1D0E&p=269351&pn=1&searchId=6cb6d804e8c2d0cca41f0eed698c3a54&searchtype=0
HIPPOTRAGUS NIGER ROOSEVELTI
mature females:
https://www.alamy.com/stock-photo-adult-female-sable-antelope-in-the-shimba-hills-reserve-mombasa-kenya-18913006.html?imageid=4CEF7928-8E87-49EF-9D29-37727F06B00D&p=30436&pn=1&searchId=5025017ea04e94a5648cb5917feeee17&searchtype=0
https://www.safaribookings.com/shimba-hills/wildlife-photos#photo17
http://www.africaimagelibrary.com/media/75898f9a-1d00-11e0-9f21-f72837a033d8-sable-antelope-hippotragus-niger-roosevelti-shimba-hills-nat
https://www.alamy.com/stock-photo-sable-antelope-hippotragus-niger-roosevelti-shimba-hills-national-11844414.html?imageid=EA431439-A82C-4859-B596-3F4C278E882F&p=74587&pn=1&searchId=5025017ea04e94a5648cb5917feeee17&searchtype=0
https://www.alamy.com/stock-photo-adult-female-sable-antelope-in-the-shimba-hills-reserve-mombasa-kenya-18913775.html?imageid=D9A707E6-7779-4CC7-9457-39331867AC7A&p=30436&pn=1&searchId=5025017ea04e94a5648cb5917feeee17&searchtype=0
juveniles:
http://www.africaimagelibrary.com/media/ce887134-1cff-11e0-baba-4bc06b3ad738-sable-antelope-hippotragus-niger-roosevelti-shimba-hills-nat
https://www.alamy.com/stock-photo-adult-female-sable-antelope-in-the-shimba-hills-reserve-mombasa-kenya-18912777.html?imageid=025270AF-2961-4FAF-B4F0-2D7D9D6C5056&p=30436&pn=1&searchId=5025017ea04e94a5648cb5917feeee17&searchtype=0
https://www.britannica.com/animal/roan-antelope
https://www.alamy.com/stock-photo-roan-antelope-running-africa-87078628.html
https://www.sciencephoto.com/media/1254315/view/roan-antelope
https://www.pinterest.com.au/pin/red-hartebeest-antelope-in-2023--4644405857770911/
https://safariclub.org/the-roosevelt-sable/
https://www.flickr.com/photos/waynekennedy/51749864505/
https://www.awf.org/wildlife-conservation/roan-antelope
http://africanwanderlust.weebly.com/roan.html
https://howieswildlifeimages.com/2022/06/07/selati-roan-antelope/
https://www.sciencephoto.com/media/728146/view/roan-antelope
Shift
https://www.dreamstime.com/stock-photo-roan-antelope-hippotragus-equinus-dry-grassland-against-blurred-natural-background-south-africa-image45175946
https://animalia.bio/roan-antelope
Always fascinated by the Angolan giant sable, though I've only seen taxidermy of some specimens at AMNH
https://m.facebook.com/bbryanpreserve/photos/at-b-bryan-preserve-we-have-a-large-herd-of-roosevelts-sable-expecting-several-c/10155837724473855/
HIPPOTRAGUS NIGER ROOSEVELTI
https://bioone.org/journals/journal-of-east-african-natural-history/volume-104/issue-1-2/028.104.0107/Historic-and-Current-Distribution-Abundance-and-Habitats-of-Roosevelts-Sable/10.2982/028.104.0107.short
https://elibrary.pu.ac.ke/bitstream/handle/123456789/751/BERNARD%20OCHIENG.pdf?sequence=1&isAllowed=y
https://www.wildlifeofkenya.com/categories/ongulates/antelope-sable/
@paradoxornithidae
https://opensiuc.lib.siu.edu/cgi/viewcontent.cgi?article=1001&context=esh_2015
http://williamfowldsdaytoday.blogspot.com/2015/06/sable-capture.html
https://www.antelopetag.com/assets/docs/Antelope/Sable.pdf
Reference:
Estes R D and Estes R K (1969) The Shimba Hills sable population. First progress report, Hippotragine Antelope Study. National Geographic Society.
Masculine rivalry in Hippotragus niger roosevelti
Page 12:
"The sable's Lateral Intimidation Display, in which two bulls stand parallel or facing with heads high, necks arched, chins in, and tails stiffly out, is most impressive."
Page 13:
"Sub-adult males...When confronted by a demonstrating mature bull, the inferior animal puts his head low, clamps his tail between his legs, and scurries around behind the displaying male...Intimidated females behave similarly."
Add a Comment