Focussing on the reticulated giraffe (Giraffa reticulata) in its real, 'pure', unhybridised form

@variani18 @capracornelius

Which iNaturalists would identify the following as the reticulated giraffe? https://www.discoverimages.com/herd-reticulated-giraffes-common-zebra-background-5743413.html#openModal and https://www.gettyimages.com.au/detail/photo/herd-of-reticulated-giraffes-in-laikipia-landscape-royalty-free-image/1046940850?adppopup=true.

I offer this Post in aid of sharpening our search-image.

Everyone knows that a diagnostic feature of the reticulated giraffe (Giraffa reticulata) is the conversion of the normal blotchiness of giraffes into a network effect (http://cannundrum.blogspot.com/2014/08/reticulated-giraffe.html and https://www.sciencephoto.com/media/989443/view/reticulated-giraffe-young-standing-close-to-its-mother and https://similarbutdifferentanimals.com/2017/08/27/kenyan-giraffes-whats-the-difference-between-a-masai-a-reticulated-and-a-rothschilds-giraffe/).

However, several features seem to have been overlooked in the literature (e.g. see https://www.inaturalist.org/journal/milewski/48447-conspicuous-features-of-colouration-in-giraffes# and https://www.inaturalist.org/journal/milewski/59814-the-puzzle-of-conspicuous-pallor-in-a-sahelian-giraffe-part-1#).

Conserving the reticulated giraffe depends on recognising its true appearance. This is complicated by the facts that

  • the best-conserved population of 'reticulated giraffe', on the Laikipia Plateau, is actually hybridised with Giraffa camelopardalis rothschildi, and
  • all populations of 'reticulated giraffe' in zoos, worldwide, are also obviously hybridised with G. camelopardalis (not necessarily ssp. rothschildi).

In view of the above, the aim of this Post is to point out the distinctive features in the appearance of the real, 'pure' reticulated giraffe.

Here we have the most uniformly-coloured and most thoroughly camouflaged of all giraffes (https://www.dreamstime.com/reticulated-giraffe-digital-painting-large-male-computer-oil-image198653708 and https://www.westend61.de/en/imageView/RHPLF07893/reticulated-giraffe-giraffa-camelopardalis-reticulata-kalama-conservancy-samburu-kenya-east-africa-africa).

The auricular and caudal flags are the same as in other giraffes. The back-of ear is a sheeny whitish (https://www.robertharding.com/preview/1-24428/reticulated-giraffe-samburu-national-reserve-kenya-east-africa/) and the tail-tassel is black (https://www.youtube.com/watch?v=4LRkGVhmXx8
https://www.canstockphoto.com/reticulated-giraffe-walking-in-the-15692006.html).

Here is a reminder of what a laryngeal flag looks like, located on the crook of the throat: https://stock.adobe.com/sk/search?filters%5Bcontent_type%3Aphoto%5D=1&filters%5Bcontent_type%3Aillustration%5D=1&filters%5Bcontent_type%3Azip_vector%5D=1&filters%5Bcontent_type%3Avideo%5D=0&filters%5Bcontent_type%3Atemplate%5D=0&filters%5Bcontent_type%3A3d%5D=0&filters%5Bcontent_type%3Aaudio%5D=0&filters%5Binclude_stock_enterprise%5D=0&filters%5Bis_editorial%5D=0&filters%5Bfree_collection%5D=0&filters%5Bcontent_type%3Aimage%5D=1&k=%22masai+giraffe%22&order=relevance&price%5B%24%5D=1&safe_search=1&limit=100&search_page=13&search_type=pagination&get_facets=0&asset_id=127433778.

There is no laryngeal flag in Giraffa reticulata:
https://www.robertharding.com/preview/817-127671/reticulated-giraffe-giraffa-camelopardalis-reticulata-samburu-national-reserve/
https://africafreak.com/reticulated-giraffe
https://animal.fandom.com/wiki/Reticulated_Giraffe?file=Giraffe1.jpg
https://www.shutterstock.com/image-photo/reticulated-giraffe-giraffa-camelopardalis-reticulata-samburu-648809500
https://www.westend61.de/en/imageView/RHPLF07894/a-portrait-of-a-reticulated-giraffe-giraffa-camelopardalis-reticulata-kalama-conservancy-samburu-kenya-east-africa-africa

Giraffa reticulata lacks the pale and/or spotless patches on the cheeks that are seen in other giraffes (see https://www.inaturalist.org/journal/milewski/60109-the-differentially-patterned-faces-of-the-various-giraffes#).

Giraffa reticulata differs from its neighbour, Giraffa tippelskirchi, in having smaller horn-tufts, and this is most noticeable in infants. In the case of the occipital horn-tufts (see https://www.inaturalist.org/journal/milewski/59906-occipital-horn-tufts-a-previously-overlooked-feature-of-certain-giraffes#), there is virtual absence in Giraffa reticulata. These features have previously been overlooked but are surely taxonomically significant.

Returning to the topic of flags, let us review the colouration of the lower legs.

The fetlocks and pasterns are pale and spotless in all giraffes. However, this does not qualify as conspicuous unless the pale spotlessness

  • is abruptly defined by relative darkness just above the fetlocks (as in the pedal flag of Giraffa tippelskirchi), or
  • extends to the whole of the lower legs (as in the pedal flag of Giraffa camelopardalis).

By these standards, there is no pedal flag in Giraffa reticulata:
https://www.dreamstime.com/reticulated-giraffe-samburu-national-reserve-feeding-kenya-image182437028
https://www.alamy.com/a-reticulated-giraffe-standing-in-the-open-at-shaba-national-reserve-in-kenya-image223136384.html

Many photos labelled as reticulata do show lower legs pale enough to qualify as a pedal flag, but these are mainly from the Laikipia region of Kenya (https://www.inaturalist.org/observations/30528961) and from zoos (https://www.gettyimages.com.au/detail/news-photo/reticulated-giraffes-seen-at-the-wroclaw-zoological-garden-news-photo/1226313463?adppopup=true and https://naturerules1.fandom.com/wiki/Reticulated_Giraffe?file=D4y0zv7-751d12ae-d3a6-478e-a05c-320ec6721756.jpg), where there has been hybridisation with Giraffa camelopardalis.

The following unhybridised individual shows the maximum paleness on the feet in the true Giraffa reticulata, which does not qualify as a pedal flag: https://focusedcollection.com/167577218/stock-photo-reticulated-giraffe-standing-on-ground.html.

The most nebulous and individually variable of the flags is the ilial flag.

Here is a reminder of what an ilial flag looks like, in Giraffa giraffa giraffa: https://www.shutterstock.com/nb/image-photo/two-giraffes-standing-bushland-chobe-flood-1282706323 and https://www.shutterstock.com/nb/image-photo/south-african-giraffe-cape-giraffa-herd-1173965401.

There is no ilial flag in Giraffa reticulata:
https://artofsafari.travel/wp-content/uploads/2020/04/Shutterstock_Kenya_Samburu_ReticulatedGiraffe.jpg
https://www.gettyimages.com.au/detail/photo/reticulated-giraffes-on-lewa-downs-royalty-free-image/534357716?adppopup=true
http://shutterstock.puzzlepix.hu/kep/1846122715.

There is also no pectoral flag in Giraffa reticulata.

Most forms of giraffes show masculine darkening in maturity (see https://www.inaturalist.org/journal/milewski/59836-the-puzzle-of-conspicuous-pallor-in-a-sahelian-giraffe-part-2-as-opposed-to-masculine-darkness#). However, I have yet to find any photo on the Web that shows this in Giraffa reticulata.

Turning to the head again, the form of the forehead and rostrum is somewhat distinctive in both sexes of Giraffa reticulata.

The bump on the forehead is relatively abrupt. In mature males, the rostrum (anterior to the forehead) tends to remain free of enlargement by ossification:

female:
https://www.istockphoto.com/photo/reticulated-giraffe-head-profile-gm177117647-1906905
https://www.gettyimages.com.au/detail/photo/reticulated-giraffe-browsing-on-acacia-leaves-royalty-free-image/520073474?adppopup=true
https://www.dreamstime.com/girafe-reticulee-giraffa-camelopardalis-reticulata-reticulated-giraffe-head-adult-behind-acacia-tree-samburu-park-kenya-image170944255

male:
https://www.alamy.com/head-portrait-of-reticulated-giraffe-giraffa-camelopardalis-reticulata-samburu-national-reserve-kenya-africa-image262992203.html
https://www.gettyimages.com.au/detail/news-photo/close-up-of-two-reticulated-giraffes-in-the-samburu-news-photo/1053083674?adppopup=true
https://www.dreamstime.com/reticulated-giraffe-giraffa-camelopardalis-reticulata-bird-its-neck-red-billed-oxpecker-buphagus-erythrorhynchus-samburu-image196305808
https://www.alamy.com/stock-photo-reticulated-giraffe-head-shot-samburu-national-reserve-kenya-africa-31573358.html
https://www.gettyimages.com.au/detail/news-photo/reticulated-giraffe-giraffa-camelopardalis-reticulata-close-news-photo/578258890?adppopup=true
https://www.gettyimages.com.au/detail/photo/reticulated-giraffe-portrait-samburu-national-royalty-free-image/1311465280?adppopup=true

Compare the latter with mature males of Giraffa tippelskirchi, in which not only the forehead bump but also the rostrum become ossified: https://www.alamy.com/close-up-view-of-the-head-of-a-male-giraffe-in-profile-image338486132.html. The following pair of photos summarises the differences: https://www.istockphoto.com/photo/giraffe-in-east-tsavo-park-in-kenya-gm648585952-117758575 vs https://www.istockphoto.com/photo/giraffe-close-up-head-gm531121873-55115448.

Another difference between Giraffa reticulata and the hybrid population in the Laikipia region is that, in the latter, some individual mature males develop pallor on the head (e.g. https://www.gettyimages.com.au/detail/news-photo/male-reticulated-giraffe-stands-in-the-lewa-wildlife-news-photo/1234044912?adppopup=true).

Having begun this Post with a test, let me end it with another along similar lines. iNaturalists, how would you identify the following? https://www.gettyimages.com.au/detail/photo/giraffes-walking-royalty-free-image/522081236?adppopup=true.

Publicado el 19 de noviembre de 2021 a las 09:22 PM por milewski milewski

Comentarios

Anotado por milewski hace cerca de 2 meses

@capracornelius

Reference: Goldstein (2002, https://books.google.com.au/books/about/Sensation_and_Perception.html?id=YQohAQAAIAAJ&redir_esc=y)

This author discusses, on pages 158-160, the topic of 'figure-ground perception', and in particular 'figure-ground segregation', with reference to 'Gestalt principles'. He illustrates the question of 'reversible figure-ground displays', in Figures 5.25, 5.26, 5.27, and 5.28.

See https://www.interaction-design.org/literature/topics/gestalt-principles?srsltid=AfmBOoqegprAOPTzqI_RCUK-bEYHYvwsmyOpiKGwCXfXlz67G7nko7wo and https://www.toptal.com/designers/ui/gestalt-principles-of-design#:~:text=There%20are%20six%20individual%20principles,order%20(also%20called%20pr%C3%A4gnanz) and https://www.verywellmind.com/gestalt-laws-of-perceptual-organization-2795835 and https://www.usertesting.com/blog/gestalt-principles and https://www.smashingmagazine.com/2014/03/design-principles-visual-perception-and-the-principles-of-gestalt/ and http://www.scholarpedia.org/article/Gestalt_principles and https://maze.co/blog/gestalt-principles/ and https://www.lyssna.com/blog/gestalt-design-principles/.

Based on the above, the reticulated giraffe can be seen as qualitatively different from other giraffes.

In most giraffes, we perceive the 'ground-colour' as pale, figured by the dark blotches/spots (https://www.alamy.com/koure-niger-close-up-of-giraffes-skin-pattern-giraffa-camelopardalis-peralta-note-scars-and-wounds-image439986276.html and https://www.alamy.com/koure-niger-close-up-of-giraffes-skin-pattern-giraffa-camelopardalis-peralta-note-scars-and-wounds-image439986219.html).

However, in the reticulated giraffe, it is the dark that seems to be the 'ground-colour', figured by pale netting (https://www.amazon.com.au/Close-up-Reticulated-Giraffe-Markings-Poster/dp/B00GF1FQ7U and https://stock.adobe.com/images/a-close-up-shot-of-the-pattern-of-a-reticulated-giraffe-in-the-african-wilderness-animal-and-texture-concept/300680224 and https://www.shutterstock.com/image-photo/reticulated-giraffe-pattern-634128872 and https://es.storyblocks.com/video/stock/close-up-of-a-reticulated-giraffes-giraffa-reticulata-skin-pattern-while-swishing-its-tail-around-during-the-afternoon-in-kenya-348769780 and https://www.dreamstime.com/reticulated-giraffe-giraffa-reticulata-close-up-photography-giraffe-skin-dark-brown-spot-white-surrounding-skin-image186274996 and https://www.sciencephoto.com/media/110063/view/hide-of-a-reticulated-giraffe and https://www.shutterstock.com/image-photo/reticulated-giraffe-neck-showing-pattern-giraffa-99404069 and https://www.istockphoto.com/photo/reticulated-giraffe-skin-gm535195779-57314626).

Anotado por milewski hace 23 días

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