Why Lupulella adusta could be called the baffledog

The mainly nocturnal side-striped jackal (Lupulella adusta, https://en.wikipedia.org/wiki/Side-striped_jackal and https://www.ewt.org.za/wp-content/uploads/2019/02/7.-Side-striped-Jackal-Canis-adustus_LC.pdf) blends into the background, even by day (see https://www.gettyimages.co.nz/detail/photo/side-striped-jackal-has-the-perfect-camouflage-to-royalty-free-image/1169039775?adppopup=true and https://www.gettyimages.co.nz/detail/photo/side-striped-jackal-forages-for-food-in-a-drought-royalty-free-image/1166516845?adppopup=true). However, the patterns of its colouration suggest an anti-predator strategy based on 'buying time with confusion' once spotted.

The appearance of this species is so individually and ontogenetically variable that - given its secretive ways and sparse populations - the superior predators in its habitat are unlikely to be able to recognise it immediately. This would tend to stall any attack, giving the side-striped jackal precious seconds to slip away.

First let us look at individual variation in the tail, which includes bushiness (e.g. see https://www.inaturalist.org/observations/68194156), darkness, and the presence of a pale tip.

There is a large pale tail-tip in https://www.flickr.com/photos/momathew/7581208970 and https://www.ipmimages.org/browse/detail.cfm?imgnum=1589027 and https://www.flickr.com/photos/mustafakasapoglu/20358557743 and https://species.wikimedia.org/wiki/Canis_adustus#/media/File:Side-striped_Jackal.jpg and https://www.shutterstock.com/nb/image-photo/sidestriped-jackal-south-africa-166909106 and https://retrieverman.files.wordpress.com/2012/05/side-striped-jackal.jpg. By contrast this is absent in https://www.flickr.com/photos/willievs/9183592078 and https://www.shutterstock.com/nb/image-photo/side-striped-jackal-well-camouflaged-1435456526 and https://www.inaturalist.org/observations/40303484 and https://www.alamy.com/side-striped-jackal-canis-adustus-malamala-game-reserve-south-africa-image345573267.html and https://www.agefotostock.com/age/en/details-photo/side-striped-jackal-canis-adustus-okavango-botswana-s/FHR-10605-00007-075 and https://www.gettyimages.co.nz/detail/photo/side-striped-jackal-mother-with-pup-canis-adustus-royalty-free-image/128113393?adppopup=true and https://www.zoochat.com/community/media/kaffa-side-striped-jackal-lupulella-adusta-kaffensis.520268/ and https://www.inaturalist.org/observations/9364508.

Let us turn now to the individual variation in the pattern on the flank and haunch.

In some individuals there is virtually no banding: https://www.gettyimages.co.nz/detail/news-photo/botswana-okavango-delta-moremi-wildlife-reserve-side-news-photo/453332312?adppopup=true and https://www.inaturalist.org/observations/7102563. In others there is a definite pale band sandwiched between two dark bands: https://www.gettyimages.co.nz/detail/photo/side-striped-jackals-canis-adustus-standing-jackal-royalty-free-image/128117577?adppopup=true and https://www.agefotostock.com/age/en/details-photo/side-striped-jackal-canis-adustus-chobe-national-park-botswana-africa/MEV-10848950.

Other individuals again show various combinations and intermediate patterns. The pale band varies in shape and orientation.

The following illustrate these bewildering variations, which only partly correlate with subspecies: https://www.naturepl.com/stock-photo-side-striped-jackal-canis-adustus-standing-in-grassland-kopjes-image01312252.html and https://www.inaturalist.org/observations/85742147 and https://www.gettyimages.co.nz/detail/photo/side-striped-jackal-showing-characteristic-side-royalty-free-image/128118754?adppopup=true and https://www.gettyimages.co.nz/detail/photo/side-striped-jackal-royalty-free-image/680297560?adppopup=true and https://www.gettyimages.co.nz/detail/photo/side-striped-jackal-hunting-for-food-canis-adustus-royalty-free-image/128113397?adppopup=true and https://www.inaturalist.org/observations/53813876.

There is also independent variation in the presence and shape of a subsidiary pattern on the haunch: https://www.zoochat.com/community/media/kaffa-side-striped-jackal-lupulella-adusta-kaffensis.520271/ and https://www.inaturalist.org/observations/49457367.

Finally turning to ontogenetic variation, the following show how different juveniles look from the adults above: https://www.gettyimages.co.nz/detail/photo/side-striped-jackal-pup-two-months-old-canis-royalty-free-image/128113395?adppopup=true and https://www.gettyimages.co.nz/detail/photo/side-striped-jackal-royalty-free-image/1185518352?adppopup=true and https://www.alamy.com/side-striped-jackal-canis-adustus-standing-in-a-forest-kenya-image376771778.html and https://www.biolib.cz/en/image/id379867/ and http://resizeme.club/imageresizer-219_01221912.html.

The two species of Lupulella differ in their dependence on cover, their times of activity, and their diets. Both have odd colouration - particularly on the flanks - for canids. However, the conspicuous colouration of L. mesomelas (http://justfunfacts.com/wp-content/uploads/2016/07/jackal.jpg and see my Post of July 24, 2021, titled 'Why is the black-backed jackal the only carnivore marked like a gazelle?') makes sense for a partly diurnal species of open vegetation, which tends to hunt relatively large prey cooperatively.

In the case of the timid, omnivorous side-striped jackal, the oddness is mainly in the inconsistency - which has the opposite effect from promoting rapid recognition. This capitalises on the chances that superior predators will not yet have formed a search-image for the species, while at the same time boosting the number of encounters needed for them to form a search-image.

Publicado por milewski milewski, 07 de agosto de 2021

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