The six flags (conspicuous features of adaptive colouration) in the various spp. of giraffes (Giraffa)

@variani18 @davidbygott @capracornelius

Also see https://www.inaturalist.org/journal/milewski/69597-a-new-idea-for-how-colouration-of-giraffes-giraffa-achieves-camouflage#

Inconspicuous colouration allows large mammals to be overlooked by predators.

However, it is possible for these animals to communicate socially by means of flags.

Flags are defined as relatively small-scale patterns of colouration, restricted to certain parts of the anatomy, which become conspicuous when the animal moves.

The arrangement of this conspicuous colouration on the figure is such that the feature in question can be displayed to companions without negating the overall crypsis/camouflage.

The location of flags on particularly mobile body-parts - such as the tail, ear pinnae, and feet - allows such communication to be activated by movement, and de-activated when the animal 'freezes' in stationary self-concealment.

Giraffes (Giraffa, see https://giraffeconservation.org/giraffe-species/) are the largest land mammals with camouflage-colouration (https://www.dreamstime.com/stock-photo-sizing-him-up-etosha-national-park-namibia-young-playful-cheetah-giraffe-attempt-to-play-image94704382).

Therefore, their flags potentially facilitate discrete communication, intraspecifically, over distances of hundreds of meters.

Flags in giraffes comprise

  • one dark flag, viz a caudal flag, and
  • five pale flags.

The pale flags of giraffes (auricular, pedal, laryngeal, ilial, and pectoral) are relatively subtle. This is mainly because they

  • depend partly on sheen effects, and
  • can be activated by slight movements.

CAUDAL FLAG

https://www.collinsdictionary.com/dictionary/english/caudal

A caudal flag in giraffes consists of a consistently black tail-tassel (https://www.inaturalist.org/observations/139741472).

This flag is activated by vigorous movement of the tail, particularly while the animal is running (https://www.youtube.com/watch?v=WsaOn85TqUE and https://www.youtube.com/watch?v=MuanfpL1o18 and https://www.canstockphoto.com/giraffe-running-on-african-plains-52505825.html).

The following shows that the caudal flag is not activated in self-defence while standing: https://www.youtube.com/watch?v=qCG9y7Sh404.

AURICULAR FLAG

The auricle (= pinna) is the visible portion of the outer ear (https://www.merriam-webster.com/dictionary/auricle)

The auricular flag in giraffes consists of a pale, sheeny surface on the back-of-ear (https://www.inaturalist.org/observations/10445552). This accentuates the movement of figures walking away from the observer.

Because this flag is restricted to the posterior surface of the ear pinna, it is more precisely called a posterior auricular pinna.

The auricular flag is relatively poorly developed in Giraffa tippelskirchi tippelskirchi (in which the sheen effect seems weak) and Giraffa camelopardalis peralta (in which the pale feature seems hardly noticeable given that the whole head tends to be pale, see https://www.inaturalist.org/journal/milewski/59814-the-puzzle-of-conspicuous-pallor-in-a-sahelian-giraffe-part-1#).

Giraffa camelopardalis rothschildi

https://www.inaturalist.org/observations/147186162
https://www.gettyimages.com.au/detail/photo/three-giraffes-are-going-towards-a-forest-royalty-free-image/918726918?adppopup=true
https://www.istockphoto.com/photo/herd-of-rothschilds-giraffe-uganda-gm157426768-8892084
https://www.istockphoto.com/photo/baringo-giraffe-gm1340762784-420737767
https://www.istockphoto.com/photo/wild-rothschild-giraffe-in-kenya-gm1168571578-322707097
https://www.hemis.fr/image-photo/557797/kenya-great-rift-valley-lake-nakuru-national-park-baringo-giraffe-giraffa-cameleopardalis.html
https://www.mindenpictures.com/stock-photo-rothschilds-giraffes-giraffa-camelopardalis-rothschildi--in-savanna-naturephotography-image90720680.html
https://www.zoochat.com/community/media/reticulated-giraffe.478769/

Giraffa tippelskirchi tippelskirchi

https://www.istockphoto.com/photo/masai-giraffe-savannah-gm478419854-67337859
https://www.inaturalist.org/observations/66937412
https://www.dreamstime.com/stock-photo-giraffe-serengeti-image464040
https://www.inaturalist.org/observations/2308366
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=21&search_type=pagination&get_facets=0&asset_id=99370073
https://www.inaturalist.org/observations/73621039
https://www.inaturalist.org/observations/66514114
https://www.inaturalist.org/observations/30264129
https://www.istockphoto.com/photo/giraffes-in-masai-mara-reserve-gm1314002621-402348612

Giraffa tippelskirchi thornicrofti

https://www.robertharding.com/preview/1320-47/herd-giraffe-stare-distance-south-luangwa-national-park/
https://www.inaturalist.org/observations/14509328

Giraffa giraffa giraffa

https://www.inaturalist.org/observations/4890790
https://www.inaturalist.org/observations/17749944
https://www.inaturalist.org/observations/66782849
https://www.inaturalist.org/observations/75826277
https://www.inaturalist.org/observations/16714252
https://upload.wikimedia.org/wikipedia/commons/4/43/Giraffes_in_Kruger_National_Park.jpg
https://www.inaturalist.org/observations/73879596
https://www.agefotostock.com/age/en/details-photo/south-african-giraffes-giraffa-giraffa-giraffa-feeding-on-leaves-kgalagadi-transfrontier-park-northern-cape-south-africa-africa/ZI6-3020214
https://www.inaturalist.org/observations/51578325
https://www.inaturalist.org/observations/19998991
https://www.inaturalist.org/observations/11268385
https://www.inaturalist.org/observations/75582773

LARYNGEAL FLAG

https://www.merriam-webster.com/dictionary/laryngeal

A laryngeal flag, consisting of a pale tract between the crook of the throat and the base of the ear, occurs in several forms of giraffe, subject to individual variation. It is clearest and most consistent in Giraffa tippelskirchi.

The laryngeal flag works in conjunction with a conspicuous paleness on the cheeks that occurs in several forms of giraffe, subject to individual variation and illumination (e.g. https://www.inaturalist.org/observations/17534088 and https://www.istockphoto.com/photo/giraffes-in-tsavo-east-national-park-tsavo-west-and-amboseli-gm1199696012-343350688 and https://www.alamy.com/stock-photo-masai-giraffe-giraffa-camelopardalis-tippelskirchi-masai-mara-park-111555190.html and https://www.dreamstime.com/royalty-free-stock-image-giraffe-feeding-acacia-tree-tongue-out-image36603276 and https://www.freepik.com/premium-photo/giraffe-near-large-tree-masai-mara-kenya_12050017.htm#&position=8 and https://www.alamy.com/stock-photo-southern-giraffe-giraffa-camelopardalis-giraffa-bull-collects-flowers-73318924.html).

The following show that a laryngeal flag is produced by alteration of both the matrix (= ground colour) and the spotting:
https://www.istockphoto.com/photo/birds-on-giraffes-neck-gm972266594-264701207 and https://www.shutterstock.com/nb/image-photo/giraffe-maasai-mara-kenya-1342085414.

At the crook of the throat, the matrix (= ground colour) is converted from fawn to whitish, and the spotting is largely absent.

Giraffa tippelskirchi tippelskirchi

https://www.gettyimages.com.au/detail/photo/giraffe-and-baobab-tree-under-blue-sky-in-ruaha-royalty-free-image/1198712362?adppopup=true
https://www.gettyimages.com.au/detail/photo/giraffe-and-baobab-tree-under-blue-sky-in-ruaha-royalty-free-image/1198712301?adppopup=true
https://www.gettyimages.com.au/detail/photo/giraffe-royalty-free-image/553182873?adppopup=true
https://www.istockphoto.com/photo/giraffe-and-baobab-tree-under-blue-sky-in-ruaha-national-park-in-tanzania-gm1198712362-342691751
https://www.natgeokids.com/wp-content/uploads/2016/11/Giraffe-Facts-2.jpg
https://www.dreamstime.com/adorable-wild-giraffe-beautiful-pattern-coat-cute-giraffe-photo-has-dark-light-brown-fur-image112071996
https://www.istockphoto.com/photo/masai-giraffe-serengeti-tanzania-africa-gm460390571-31595452
https://www.masterfile.com/image/en/600-03814912/masai-giraffe-masai-mara-national-reserve-kenya
https://fineartamerica.com/featured/reticulated-giraffe-grazing-on-small-jean-michel-labat.html
https://fineartamerica.com/featured/maasai-giraffe-on-the-move-james-warwick.html

Giraffa giraffa giraffa

https://www.inaturalist.org/observations/20390103
https://peapix.com/bing/9393
https://pixabay.com/photos/giraffe-africa-nature-467166/
https://www.everypixel.com/image-8596535059091917737
https://www.dreamstime.com/royalty-free-stock-photo-giraffe-image14687355
https://www.istockphoto.com/photo/giraffe-gm488890075-39889906
https://www.inaturalist.org/observations/5141178

Giraffa giraffa angolensis

https://www.dreamstime.com/royalty-free-stock-images-giraffe-namibia-image15159409

The laryngeal flag is continuous with the auricular flag in certain perspectives (https://www.dreamstime.com/giraffe-calf-its-mom-maasai-mara-national-reserve-kenya-her-baby-african-savannah-image167332536 and https://www.dreamstime.com/stock-images-whos-coming-giraffes-alert-wildlife-heads-ears-above-acacia-trees-to-see-looking-down-valley-hearing-vehicles-image31623364).

However, the laryngeal flag is activated by the movements of foraging (https://www.dreamstime.com/stock-image-giraffe-eating-image22388031 and https://www.dreamstime.com/giraffe-vast-green-savanna-chews-bushes-real-pretty-day-image216044996 and https://www.inaturalist.org/observations/94246126).

PEDAL FLAG

https://www.merriam-webster.com/medical/pes

A pedal flag occurs in two of the four species of giraffes. This

The following, of Giraffa tippelskirchi, show laryngeal and pedal flags within the same photos: https://www.istockphoto.com/photo/masai-giraffe-gm1257170721-368333347 and https://fineartamerica.com/featured/lake-manyara-giraffe-edmund-hall.html.

In Giraffa camelopardalis, the pedal flag extends to the whole of the lower legs. Furthermore, it remains even in mature males in which there has been a general darkening (https://www.istockphoto.com/photo/female-giraffe-with-a-baby-in-the-savannah-gm669752120-122872959 and https://www.inaturalist.org/observations/155008498 and https://www.inaturalist.org/observations/129218340 and https://www.inaturalist.org/journal/milewski/59836-the-puzzle-of-conspicuous-pallor-in-a-sahelian-giraffe-part-2-as-opposed-to-masculine-darkness#).

Giraffa camelopardalis rothschildi

https://www.shutterstock.com/nb/image-photo/rotschild-giraffes-lake-nakuru-national-park-392713453
https://www.dreamstime.com/royalty-free-stock-photos-single-african-giraffe-image3482588
second photo in https://www.africanbudgetsafaris.com/blog/facts-about-giraffes/#gallery/https://d2g6byanrj0o4m.cloudfront.net/images/15613/giraffe_running.jpg/
https://www.dreamstime.com/royalty-free-stock-photography-giraffe-herd-savannah-image27232567
https://www.twenty20.com/photos/130370da-9873-4cbf-b7b6-5b521bfcd379
https://www.picfair.com/pics/06014049-rothchild-s-giraffe-giraffa-camelopardalis-nakuru-district-of-the-rift
https://society6.com/product/giraffe-animal-on-the-serengeti-national-park-tanzania-country-east-africa_stretched-canvas
https://www.istockphoto.com/photo/rothschild-giraffe-under-rainy-weather-condition-gm184982911-18702556
https://www.istockphoto.com/photo/rothschilds-giraffe-giraffa-camelopardalis-rothschildi-gm1183152375-332545504
https://www.istockphoto.com/photo/giraffes-herd-in-savannah-gm1166262329-321217655
https://www.istockphoto.com/photo/rothschilds-giraffes-gm514615669-47646538
https://www.alamy.com/rothschilds-giraffe-giraffa-camelopardalis-rothschildi-adult-walking-on-savanna-murchison-falls-national-park-uganda-november-image243664115.html
https://twitter.com/AWF_Official/status/1118076622333259777/photo/1
https://dissolve.com/stock-photo/Rothschild-Giraffe-eating-Lake-Nakuru-National-Park-Kenya-royalty-free-image/101-D256-13-351
https://twitter.com/AWF_Official/status/1118076622333259777.

In Giraffa tippelskirchi, the pedal flag is restricted to the pasterns and fetlocks (https://www.alamy.com/stock-photo-red-billed-oxpecker-buphagus-erythrorhynchus-pair-on-giraffe-giraffa-125509879.html).

Giraffa tippelskirchi tippelskirchi

https://www.alamy.com/stock-photo-masai-giraffe-giraffa-camelopardalis-tippelskirchi-males-fighting-125429292.html
https://www.shutterstock.com/nb/image-photo/masai-giraffe-maasai-known-kilimanjaro-largest-91262810
https://www.dreamstime.com/royalty-free-stock-photo-giraffe-image17934475
https://www.inaturalist.org/observations/86665608
https://www.dreamstime.com/giraffe-serengeti-plains-tanzania-africa-great-migration-giraffe-serengeti-plains-tanzania-africa-northeastern-area-near-image158533093
https://www.gettyimages.com.au/detail/photo/safari-in-kenya-a-giraffe-is-watching-in-the-royalty-free-image/1203198284?adppopup=true
https://www.dreamstime.com/stock-photography-giraffe-masai-mara-image17479462
http://scanbird.com/Mammals/Africa/Giraffe/slides/Manyara%20giraf00.html
https://pixels.com/featured/the-garden-of-eden-ndutu-jeffrey-c-sink.html
https://en.wikipedia.org/wiki/Masai_giraffe#/media/File:Young_Maasai_Giraffes.jpg
https://es.123rf.com/photo_35909720_giraffes-in-lake-manyara-national-park-tanzania.html
https://www.dreamstime.com/large-giraffe-eats-leaves-tall-tree-masai-mara-kenya-large-giraffe-eats-leaves-tall-tree-masai-mara-kenya-africa-image116519367
https://www.alamy.com/a-giraffe-looks-at-the-camera-while-another-giraffe-looks-away-image433963305.html
https://fineartamerica.com/featured/safari-in-kenya-a-giraffe-is-watching-in-the-savannah-blue-sky-cavan-images.html
https://www.dreamstime.com/stock-images-giraffe-giraffa-camelopardalis-image10804454
https://www.masterfile.com/image/en/700-06645585/herd-of-masai-giraffes-giraffa-camelopardalis-tippelskirchi
a photo found by scrolling through http://www.gondwanatoursandsafaris.com/countries/kenya/.

Please compare the following versions of a pedal flag:

ILIAL FLAG

https://en.wikipedia.org/wiki/Ilium_(bone)

The ilial flag is a nebulously pale and sheeny area on the hindquarters, offset by a dark, anti-sheen effect on the rump above it. It can work in conjunction with the caudal flag (e.g. https://www.inaturalist.org/observations/27848519). However, of all the flags it is - dependent on individual and illumination - the one most visible at a distance (e.g. https://www.inaturalist.org/observations/16496739).

In the following of Giraffa giraffa giraffa, one individual shows the ilial flag while the other nicely shows how much more conspicuous the ear pinna becomes when its posterior surface appears: https://www.inaturalist.org/observations/11260139.

The following also shows a combination of the auricular flag and the ilial flag in Giraffa giraffa giraffa: https://www.inaturalist.org/observations/33149396.

Giraffa giraffa giraffa

https://www.inaturalist.org/observations/40949059
https://www.istockphoto.com/photo/rothschild-giraffe-in-natural-habitat-gm1291905028-386882584
https://www.robertharding.com/preview/741-4431/southern-giraffe-giraffa-camelopardalis-chief-island-moremi-game/
third photo in https://www.thecrowdedplanet.com/things-to-do-in-botswana-one-week-itinerary/
https://www.inaturalist.org/observations/70309925 and https://es.123rf.com/photo_6761884_giraffes-in-chobe-national-park-botswana.html
https://www.agefotostock.com/age/en/details-photo/2-giraffes-giraffa-camelopardalis-okavango-delta-botswana/AAM-AAES79257
https://www.flickr.com/photos/27727912@N03/49219139176/
https://www.flickr.com/photos/chriscorbet/22715521997/
https://www.flickr.com/photos/manuelromaris/50203975892
https://www.123rf.com/photo_111847852_giraffe-in-kruger-national-park-south-africa-specie-giraffa-camelopardalis-family-of-giraffidae.html
https://www.shutterstock.com/nb/image-photo/wild-giraffe-african-savannah-typical-landscape-1560945341
https://www.alamy.com/south-african-giraffe-chobe-botswana-safari-image343877708.html
https://www.alamy.com/southern-giraffe-giraffa-giraffa-roaming-herd-kalahari-desert-kgalagadi-transfrontier-park-south-africa-image184078576.html
https://www.alamy.com/giraffe-giraffa-camelopardarlis-giraffa-side-view-of-an-adult-walking-in-the-savannah-mpumalanga-south-africa-image355185321.html

PECTORAL FLAG

https://www.merriam-webster.com/dictionary/pectoral

The pectoral flag is a paired pale patch on the anterior surface of the junction between forelegs and chest. It is most noticeable in mature males, which tend to be otherwise darkened.

Giraffa giraffa giraffa

https://www.inaturalist.org/observations/72922453
https://www.inaturalist.org/observations/86379216
https://www.inaturalist.org/observations/44924108
https://www.inaturalist.org/observations/31409053
https://www.dreamstime.com/stock-photos-adult-bull-giraffe-image22166473

DISCUSSION

No form of giraffe possesses all of the above flags.

Considering only the pale flags:

An ilial flag and a pectoral flag occur only in Giraffa giraffa, and are individually variable. The following shows four of the flags possessed by Giraffa giraffa giraffa, within one photo: https://www.dreamstime.com/stock-photo-giraffe-family-two-tiny-babies-small-enjoying-winter-sun-group-adults-image43592890.

The distribution, by geographic area, is as follows:

  • species camelopardalis, found from West Africa to western Kenya, has an auricular flag (except in subspecies peralta) and a pedal flag (in attenuated form);
  • species reticulata, found in northern Kenya, has only an auricular flag;
  • species tippelskirchi, found from Kenya to eastern Zambia, has an auricular flag (perhaps relatively poorly developed), a laryngeal flag, and a pedal flag (in accentuated form); and
  • species giraffa, found in southern Africa, has an auricular flag (perhaps relatively poorly developed), a laryngeal flag (relatively poorly developed), an ilial flag, and a pectoral flag, the last two being restricted to subspecies giraffa (task: check ssp. angolensis).

Thus, a noteworthy aspect of the pale flags - as opposed to the consistently dark tail-tassel that constitutes the caudal flag - is the variation among the species and subspecies of giraffes.

(The following shows the caudal and auricular flags in action simultaneously, which again enhances conspicuousness because of the contrast between dark and pale: https://www.shutterstock.com/nb/video/clip-2484515-wild-group-extremely-endangered-rothschild-giraffe-giraffa.)

The only pale flag common to all species of giraffes is a posterior auricular flag. In the case of Giraffa reticulata (see https://i.redd.it/3ju4klr11lv31.jpg and https://www.masterfile.com/image/en/841-02824842), this is the only conspicuously pale feature on the whole figure, viewed from any angle.

Publicado el marzo 31, 2021 02:25 MAÑANA por milewski milewski

Comentarios

Very interesting, many thanks for posting this!

Publicado por anasacuta hace más de 2 años

@anasacuta You are most welcome.

Publicado por milewski hace más de 2 años

Fascinating observations made here. Thanks for the lesson!

Publicado por goodlordbird hace más de 2 años

@goodlordbird Hi Nathan, I'm so glad that you find this informative, with best wishes from Antoni.

Publicado por milewski hace más de 2 años

The following show that - in contrast to its clear development in Giraffa tippelskirchi - the laryngeal flag is residual/incipient in Giraffa camelopardalis rothschildi:

https://www.inaturalist.org/observations/203590483

https://www.inaturalist.org/observations/203590427

https://www.inaturalist.org/observations/194817116

Conspicuous mainly by virtue of its connection to the posterior auricular flag:

https://www.inaturalist.org/observations/188008586

https://www.inaturalist.org/observations/174436007

https://www.inaturalist.org/observations/142540218

Publicado por milewski hace 8 días
Publicado por milewski hace 8 días

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