The tsessebe as a mudbuck

@tonyrebelo @jeremygilmore @tandala @paradoxornithidae @botswanabugs @jwidness @zarek @simontonge @michalsloviak

For most naturalists familiar with the tsessebe (Damaliscus lunatus lunatus), the image of this alcelaphin (https://en.wikipedia.org/wiki/Alcelaphinae) is far from a 'stick-in-the-mud'.

Here we have a lean antelope as fleet as a racehorse and even lighter on its feet, associated with firm ground where the only limitation is stamina.

Furthermore, the small fecal pellets of the tsessebe (https://www.naturefootage.com/video-clips/JLM170303_0359/tsessebe-standing-defecting and https://www.inaturalist.org/observations/112131138) indicate a species adapted to dry conditions.

So, it is surprising to find, on closer examination, that the tsessebe is peculiarly 'muddy'.

Had the tsessebe not already been named after the Setswana vernacular (https://en.wikipedia.org/wiki/Tswana_language), it might aptly-enough be called the 'mudbuck' (or, in Afrikaans, 'modderbok').

The association of the tsessebe with mud includes

The following additional photos show the tsessebe with its pelage bedecked with mud:

https://www.alamy.com/stock-photo-tsessebe-antelope-in-southern-african-savanna-141669385.html?imageid=B1CD8529-1B3C-4E1C-9D23-49BCE9234784&p=291902&pn=2&searchId=60e559f776350f3aa551632b23562389&searchtype=0

https://www.inaturalist.org/observations/150099139

https://www.inaturalist.org/observations/14220603

https://www.inaturalist.org/observations/8180095

https://www.alamy.com/rare-tsessebe-antelope-damaliscus-lunatus-at-a-waterhole-south-africa-image180857620.html

https://www.alamy.com/stock-photo-rare-tsessebe-antelope-damaliscus-lunatus-south-africa-58368578.html

I have yet to see similar mud-bedecking in the topi (Damaliscus jimela), despite the two taxa being widely regarded as belonging to the same species.

Adult males of both the topi and the tsessebe adorn the horns with mud (https://www.alamy.com/stock-photo-topi-masai-mara-getting-ready-to-fight-for-his-harem-92999365.html?imageid=738ECA19-2EFC-4B03-B124-D2668ECB02DD&p=284001&pn=1&searchId=bf1e71fcf2ea53c3266b9674b4a7c2d8&searchtype=0).

However, the tsessebe uses mud also to bedeck its pelage, to an extent unknown in the topi.

Furthermore, in the tsessebe,

Please compare:

Tsessebe

https://www.dreamstime.com/stock-photo-muddy-tsessebe-portrait-antelope-has-had-red-mudbath-image74100059 and https://www.alamy.com/stock-photo-portrait-of-a-tsessebe-antelope-that-has-had-a-red-mudbath-170259076.html?imageid=02E0BADE-66C9-4F06-BB26-192E662C72C2&p=291902&pn=7&searchId=b5919b63c16a90d70b8f3874012c89a6&searchtype=0 and https://www.alamy.com/stock-photo-a-group-of-tsessebe-antelope-that-have-had-a-red-mudbath-170259062.html?imageid=86B99247-BF43-4482-8CA2-06910CC95A80&p=291902&pn=6&searchId=c7d97a4328b8ff32aa812bc4af94c292&searchtype=0 and https://www.shutterstock.com/it/image-photo/tsessebe-antelope-having-mud-bath-southern-782490406 and https://www.flickr.com/photos/richardlewisjones/2318608064

Topi

https://www.gettyimages.co.uk/detail/photo/topi-antelope-damaliscus-lunatus-masai-mara-royalty-free-image/1172247501?phrase=topi%20antelope&adppopup=true and https://www.gettyimages.co.uk/detail/photo/topi-with-grass-and-mud-on-horns-royalty-free-image/522615612?phrase=topi%20antelope&adppopup=true and https://www.jkwildimages.co.uk/kenya/20w70v2f4407vwqb1d4vf6ar1cos4f and https://www.projectnoah.org/spottings/7405328

DISCUSSION

Alcelaphins are surprisingly diverse in their habits w.r.t. dust, mud, and dirt.

No alcelaphin wallows.

However,

Within Damaliscus, there is a correlation between the use of mud and the colouration,

The pigmentation/depigmentation of the bontebok (Damaliscus pygargus pygargus) is exceptionally clear and graphic, and always looks clean, with no role played by mud or dust (https://www.facebook.com/100903643309358/photos/bontebok-and-blesbok-are-two-similar-but-distinct-antelope-species-that-came-clo/1327874950612215/?locale=hi_IN). One does not even see the horns of males of the bontebok adorned with mud/earth.

At the other extreme is the tsessebe: the pelage retains the complex pattern of colouration typical of the genus. However, the pigmentation is so indistinctly differentiated that the patterns seem to have been 'muddied' in the first place, by a complex combination of brindling, sheen, and ambivalent pigmentation.

The inference is that, in some sense, the colouration of the tsessebe has evolved to be such that little is lost when the pelage is bedecked by mud. This may be the closest thing to the development of 'clothing' among ungulates that retain a full cover of hair.

Is there any other non-wallowing ruminant in which the colouration has evolved to be conferred partly by mud?

And does the above evidence not support the separation of the tsessebe from the complex of korrigum/jimela/topi/tiang, as a species rather than a mere subspecies?

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 19 de mayo de 2023 a las 12:25 AM por milewski milewski

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