The springbok (Antidorcas marsupialis) seems to qualify as possessing a facial flag, but not a caudal flag

@capracornelius

Also see https://www.inaturalist.org/journal/milewski/53340-differences-among-gazelles-in-the-structure-and-function-of-the-tail# and https://www.inaturalist.org/journal/milewski/51816-a-comparison-of-the-goitred-gazelle-and-the-springbok#

Bigalke (1972, https://www.tandfonline.com/doi/pdf/10.1080/00445096.1972.11447448), on page 336, states, under the heading "HEAD TOSSING":

"springbok often toss the head as they move off, commonly at a fast trot, when alarmed. The movement is pronounced, the head being lowered to near the ground and raised again repeatedly. It appears in other gaits as well...Head tossing is an important element of the stott and also appears in the proud trot."

Has this behaviour ever been photographed or filmed, beyond inadvertent coverage as part of stotting? (https://www.youtube.com/watch?v=FZyjiEhtBLU)

THE FACIAL FLAG OF THE SPRINGBOK

From the viewpoint of adaptive colouration, I hypothesise that the whitish pelage, covering most of the face in adults of the springbok, constitutes a facial flag (a term I have recently coined, 50 years after this paper by Bigalke was published).

https://www.freeimages.com/premium/springbok-head-1616953

https://focusedcollection.com/203469486/stock-photo-portrait-one-springbok-horns-standing.html

https://www.istockphoto.com/photo/close-up-of-a-springbok-head-etosha-national-park-namibia-gm1074515782-287659509

https://www.agefotostock.com/age/en/details-photo/springbok-antidorcas-marsupialis-portrait-kgalagadi-transfrontier-park-northern-cape-south-africa-africa/ZI6-2528944/1

All flags, in the sense of adaptive colouration in mammals, are by definition activated by motion. In this case, the activation is partly by means of head-tossing, as described by Bigalke.

The facial flag of the springbok has an ontogenetic component, being absent at birth, and fully-developed in adulthood.

The fawn-coloured markings on the face in infants and juveniles (https://depositphotos.com/253184374/stock-photo-closeup-portrait-beautiful-springbok-his.html) tend to disappear in adulthood, in both sexes.

The following are particularly clear illustrations of the difference in facial colouration between infants and their mothers:

https://www.istockphoto.com/photo/springboks-mother-and-lamb-in-the-kalahari-desert-gm1215293721-353914538?phrase=springbok%20nursing

https://www.istockphoto.com/photo/springboks-mother-and-lamb-in-the-kalahari-desert-gm1216217997-354562487?phrase=springbok%20nursing

First photo in https://mistersafari.com/khutse-game-reserve/

The following show the progressive loss of the fawn (ground-colour) from the face, with the age of the individual:

Neonate:
https://www.alamy.com/springbok-antidorcas-marsupialis-baby-resting-on-ground-using-camouflage-for-defence-kgalagadi-transfrontier-park-south-africa-image357520963.html?imageid=2300EFD8-5CB8-47AE-874A-3321150EC059&p=477095&pn=1&searchId=6d4c43606c5f5d238388a54565d6b0ae&searchtype=0Infant:https://www.alamy.com/springbok-antidorcas-marsupialis-young-lamb-resting-rainy-season-with-image153102567.html?imageid=CB4D276D-D63B-4E04-A229-4ECC4A395363&p=204862&pn=1&searchId=6d4c43606c5f5d238388a54565d6b0ae&searchtype=0

Infant/juvenile:
https://www.alamy.com/springbok-antidorcas-marsupialis-young-lamb-resting-rainy-season-with-image153102511.html?imageid=9B0A3BD9-3C07-4570-9ECA-AE218571ECAB&p=204862&pn=1&searchId=6d4c43606c5f5d238388a54565d6b0ae&searchtype=0

Juvenile just after horns appear:
https://www.alamy.com/stock-photo-young-springbok-antelopes-resting-at-etosha-national-park-located-149347112.html?imageid=BD03D04A-08E7-4886-866C-64E4F70A3BF8&p=14406&pn=1&searchId=6d4c43606c5f5d238388a54565d6b0ae&searchtype=0

Adult female:
https://www.alamy.com/stock-photo-springbok-antidorcas-marsupialis-herd-resting-in-the-kalahari-desert-26254321.html?imageid=6EB0FF4F-DD92-43C2-B1F5-9B6DCEDFCFE5&p=80871&pn=1&searchId=6d4c43606c5f5d238388a54565d6b0ae&searchtype=0

Adult male:
https://www.alamy.com/stock-photo-springbok-antidorcas-marsupialis-herd-resting-in-the-kalahari-desert-26254321.html?imageid=6EB0FF4F-DD92-43C2-B1F5-9B6DCEDFCFE5&p=80871&pn=1&searchId=6d4c43606c5f5d238388a54565d6b0ae&searchtype=0

DOES THE SPRINGBOK QUALIFY AS POSSESSING A CAUDAL FLAG?

On page 335 of the same publication, Bigalke (1972) states:

"Walther points out that the tail of all gazelles is an extremely mobile organ. In the springbok, the tail is moved from side to side incessantly while the animals feed or walk about. Tense situations, as for example when a resting herd is disturbed and the animals rise and watch the intruder, also produce active tail wagging. In flight, on the other hand, the tail is pressed up against the body between the haunches, as in Grant's gazelle (Walther 1968)."

The following hardly support Bigalke's observation that the tail is routinely wagged during walking:

https://www.dreamstime.com/stock-video-footage-springbok-antelope-herd-large-antelopes-antidorcas-marsupialis-walking-over-plains-kalahari-desert-south-africa-video37600682

https://www.pond5.com/stock-footage/item/8567891-springbok-antelope-herd-african-wildlife-safari-kalahari-des

https://www.dreamstime.com/springbok-antelopes-walking-line-kalahari-desert-herd-antidorcas-marsupialis-south-africa-video196509142

https://www.dreamstime.com/stock-video-footage-springbok-antelopes-walking-line-herd-antidorcas-marsupialis-kalahari-desert-south-africa-video75741536

https://www.shutterstock.com/it/video/clip-1328305-large-herd-springbok-antelopes-antidorcas-marsupialis-walking

https://www.pond5.com/stock-footage/item/8548432-large-herd-springbok-antelopes-kalahari-desert-south-africa

https://www.sciencephoto.com/media/k0051669/view

https://www.shutterstock.com/it/video/clip-1316965-large-herd-springbok-antelopes-antidorcas-marsupialis-walking

https://depositphotos.com/153463014/stock-video-herd-of-springbok-africa-safari.html

https://www.shutterstock.com/it/video/clip-1014601916-springbok-eating-walking

https://www.istockphoto.com/video/springbok-antelope-herd-gm473149625-23243807

https://www.dreamstime.com/stock-footage-springbok-antelope-antidorcas-marsupialis-walking-grassland-south-africa-video44273442

The following do support Bigalke's observations, but show how inconspicuous the tail is, even in motion:

https://dissolve.com/video/Herd-springbok-antelopes-Antidorcas-marsupialis-walking-royalty-free-stock-video-footage/001-D260-8-038

https://www.pond5.com/stock-footage/item/66425457-springbok-antelope-herd-natural-habitat-kalahari-south-afric

In terms of adaptive colouration, a caudal flag consists of a pattern of dark, pale, or dark/pale contrast, on and adjacent to the tail, that is not necessarily conspicuous in the stationary figure, but becomes conspicuous in motion, even at some distance.

The springbok differs from most other gazelles in that its tail

• is relatively inflexible at the base, and is never fully erected (the maximum is shown in https://www.flickr.com/photos/22115324@N02/5340742650),
• has a relatively small/sparse tassel (https://www.alamy.com/stock-photo-south-africa-mountain-zebra-national-park-springbok-tails-spinning-16434530.html),
• is not raised in alarm or fleeing, and
• is actually hidden during anti-predator displays, particularly during stotting.

Therefore, even when the springbok wags its tail in normal activity, and in mild alarm, this does not necessarily mean that this signal is significantly amplified by the colouration of the tail. A good example of such amplification is instead seen in the goitred gazelle (Gazella subgutturosa), in which the pattern is far more graphic than in the springbok (https://www.istockphoto.com/video/running-goitered-gazelle-gm473245311-26196643?phrase=gazelle%20running).

The following shows the maximum development of the dark tassel of the tail in the springbok (https://www.istockphoto.com/video/springbok-gm1453656922-489483658?phrase=springbok). However, once again, contrary to Bigalke, it is not activated during routine walking.

My findings, therefore, are that the springbok

• qualifies as possessing a facial flag (in adolescents and adults of both sexes, not in infants or juveniles), but
• does not qualify as possessing a caudal flag (owing to the tail being too slight, too inflexible, and too inert for the combination of whitish tail-stalk and dark tassel to add much to the conspicuousness of the figure).

Posted on February 24, 2023 11:56 AM by milewski