Have we missed the auricular semets shared by big cats and deer?

Felids and cervids belong to different orders of mammals. Indeed they are opposite: predators vs prey.

Because big cats and deer are categorically different, the naturalist does not expect them to be similar in their facial expressions.

And even if we realise that their ears, being mobile, are categorically more expressive than human ears, one would hardly expect the 'ear-language' of felids and deer to be directly comparable.

And yet this seems possible, at least in a few species of deer particularly capable of self-defence (see https://www.adfg.alaska.gov/index.cfm?adfg=wildlifenews.view_article&articles_id=939).

In both felids and deer, turning the ear pinna partly backward can express annoyance. And in both felids and deer, the ear-surface brought into view by such movement can be marked with dark/pale colouration to accentuate the expression.

The point I make here is simple in principle, but complicated to illustrate because of the vagaries of species-differences. One of the reasons why the felid/deer analogy has previously been overlooked is that no particular species-comparison shows it so clearly that it becomes self-evident. The naturalist would not spot the pattern without a search-image for it.

And as it happens, the required search-image emerges from several of my recent Posts. I have separately illustrated back-of-ear patterns in felids and auricular semets in deer. Put them together in the mind's eye and a realisation emerges: not only do felids have auricular semets in their own right, but the auricular semets of some felids and some deer are similar.

The genus Lynx illustrates the typical appearance of the ears in expressions of annoyance, in felids of a wide range of body sizes: https://www.shutterstock.com/image-photo/beautiful-face-lynx-clear-eyes-look-1348759271 and https://www.shutterstock.com/image-photo/lynx-portrait-nature-ears-back-328533920.

The genus Alces has essentially the same facial expression, despite the many differences between lynxes and the moose. And in both cases the position of the ears is accentuated by a certain dark/pale pattern, which the turning of the ear pinna brings into view: https://www.istockphoto.com/photo/canadian-female-moose-in-spring-gm1181486446-331396188.

The evolutionary convergence between felids and deer in expressive colouration of the ears is nowhere to be seen on the back-of-ear as viewed from directly behind the head: https://www.alamy.com/stock-photo-eurasian-lynx-lynx-lynx-ears-portrait-back-view-10882818.html and https://www.alamy.com/eurasian-lynx-lynx-lynx-head-with-tufted-ears-from-behind-captive-image60238531.html vs https://www.alamy.com/stock-photo-elk-european-moose-alces-alces-alces-elks-ears-back-view-germany-bavaria-76119845.html.

However, this is because of a simple difference in anatomy between Carnivora and ruminants: an ear-stalk is absent in the former but present in the latter. The dark/pale accentuation, being located on the ear-stalk in deer, is not visible from behind.

Can we go one step further, to suggest that potentially a photo could one day be taken by some lucky naturalist, of a standoff between big cat and deer, facing each other in antagonism with similar auricular semets mutually displayed?

This could, in our wild imagination, happen between Puma concolor and the moose in North America. Problem is: it just so happens that the puma has a particularly faint and inconsistent back-of-ear pattern for a big cat.

Or it could happen in the Russian far East, where a few individuals of the local, snow-tolerant subspecies of both tiger (Panthera tigris) and leopard (Panthera pardus) remain sympatric with the moose to this day (e.g. see https://news.cgtn.com/news/3d3d514d7a49544f31457a6333566d54/index.html).

But the only significant chance of such a photograph - a real scoop for the connoisseurs among naturalists - would be in some small reserve in India. Here both tiger and leopard still hunt the sambar (Rusa unicolor). For, of all the world's deer, the sambar most closely resembles the moose in its anterior auricular semet (perhaps shown in https://www.alamy.com/dhole-wild-dogs-found-in-india-hunting-sambar-india-image352812705.html). And, being a particularly robust deer capable of defending itself to some degree (e.g. see https://m.facebook.com/1111179082312828/photos/a.1111428672287869/1763865320377531/?type=3 and https://swordwhale.wordpress.com/2016/04/18/stuff-you-might-not-know-about-the-jungle-book/ and https://twitter.com/naturein_focus/status/1271322742625689600), it might exchange a display of semets with an inexperienced would-be predator - in the form of an adolescent of the tiger or the leopard.

פורסם על-ידי milewski milewski, אוגוסט 26, 2021 02:19 אחה"צ


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