Are the social flags of giraffes activated in infants?

The adaptive colouration of giraffes is largely inconspicuous but includes some conspicuous features, presumably in aid of social communication.

I have described these in previous Posts (e.g. https://www.inaturalist.org/journal/milewski/48447-conspicuous-features-of-colouration-in-giraffes#), pointing out that they vary individually and among the various species and subspecies of giraffes.

However, the question remains of whether the conspicuous features function at the stage of infancy.

Infants might be expected to be particularly inconspicuous because of vulnerability to predators and frequent separation from their mothers. In giraffes, however, infants older than one week hardly hide, instead becoming precocially social with their age-group in open vegetation (https://www.istockphoto.com/photo/baby-masai-giraffes-in-the-serengeti-gm1305602541-396435930).

Furthermore, the necks of infants tend to be held erect and the main horn-tufts - which are present at birth and particularly large in Giraffa tippelskirchi - seem to function as adornments rather than disguise.

For these reasons, adaptive colouration is ambivalent in infants of giraffes.

Here I examine caudal, auricular, laryngeal, and pedal flags by means of the photos available.

CAUDAL FLAG

The black tail-tassel is proportionately small at birth in all species and subspecies of giraffes (e.g. see https://www.inaturalist.org/observations/72489790). This suggests that a caudal flag is not fully functional in infants.

AURICULAR FLAG

Giraffa tippelskirchi tippelskirchi

https://www.shutterstock.com/nb/image-photo/maasai-giraffe-savanna-1357092107
https://www.alamy.com/maasai-giraffe-masai-giraffe-giraffa-camelopardalis-tippelskirchi-image64170461.html
https://www.pond5.com/stock-footage/item/95619585-mother-giraffe-gently-kissed-her-new-born-baby
https://www.inaturalist.org/observations/76942986
https://www.inaturalist.org/observations/59817921
https://www.inaturalist.org/observations/7035206

Giraffa giraffa giraffa

https://www.inaturalist.org/observations/84078831
https://www.alamy.com/stock-photo-giraffes-giraffa-camelopardalis-an-adult-and-a-calf-standing-in-the-102993230.html
https://www.alamy.com/giraffe-with-calf-pilanesberg-park-south-africa-image1154917.html
https://www.inaturalist.org/observations/30228028

The above evidence seems ambivalent, because the posterior surface of the ear pinnae is not consistently whitish in infants.

However, we have previously seen that the conspicuousness of the auricular flag is owing to a combination of depigmentation and sheen. Even in adults, the auricular flag may falter when the angle of illumination fails to give a sheen effect. The following are examples in Giraffa tippelskirchi: https://www.gettyimages.com.au/detail/photo/two-giraffes-watching-the-masai-mara-royalty-free-image/862021714?adppopup=true and 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=2&get_facets=0&search_type=pagination&asset_id=462180595 and https://www.alamy.com/stock-photo-masai-giraffe-red-billed-oxpecker-14906720.html.

I tentatively conclude that an auricular flag is present in infants of all forms of giraffe.

LARYNGEAL FLAG

Giraffa tippelskirchi tippelskirchi

https://www.alamy.com/stock-photo-close-up-of-baby-masai-giraffes-face-smiling-for-the-camera-at-the-16244508.html
https://www.alamy.com/close-up-of-adult-and-juvenile-giraffes-touching-heads-image183353682.html
https://www.thestar.com/news/gta/2020/06/21/this-little-giraffe-has-a-big-name-toronto-zoos-baby-long-legs-now-goes-by-amani-innis-dagg.html
https://www.sandiegouniontribune.com/sdut-big-baby-los-angeles-zoos-new-giraffe-is-just-2015oct22-story.html
https://www.toledoblade.com/local/2017/09/27/Toledo-Zoo-announces-birth-of-second-female-giraffe-calf/stories/20170927194
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=19&search_type=pagination&get_facets=0&asset_id=99524078

Giraffa tippelskirchi thornicrofti

https://www.alamy.com/stock-photo-female-thornicrofts-giraffe-giraffa-camelopardalis-thornicrofti-nursing-56161512.html

Giraffa giraffa giraffa

https://www.alamy.com/stock-photo-africa-botswana-chobe-national-park-adult-and-infant-giraffe-giraffa-10007133.html

As in the case of auricular flags, a laryngeal flag seems ambivalent in infants. However, the reasons are partly different because this flag depends not only on sheen but also on dark spotting of the adjacent surface of the neck. This spotting tends to be pale in infants, suggesting somewhat delayed development of a laryngeal flag.

PEDAL FLAG

Giraffa tippelskirchi tippelskirchi

https://www.pond5.com/stock-footage/item/44504762-mother-giraffe-drinking-while-baby-watches
https://www.istockphoto.com/photo/mother-giraffe-with-her-baby-gm525806063-52195590
https://www.inaturalist.org/observations/54027329
https://www.alamy.com/stock-photo-masai-giraffe-giraffa-camelopardalis-tippelskirchi-mother-nuzzling-125427186.html
https://www.alamy.com/a-newborn-giraffe-its-mother-and-another-adult-look-out-towards-the-horizon-of-the-vast-savanna-image-taken-in-the-masai-mara-kenya-image360636776.html
https://www.alamy.com/a-newborn-giraffe-stands-next-to-its-mother-and-another-another-adult-as-she-feeds-on-the-leaves-of-a-bush-image-taken-in-the-masai-mara-kenya-image360636823.html
https://www.alamy.com/a-newborn-giraffe-stands-between-its-mothers-legs-for-protection-as-she-feeds-on-the-leaves-of-a-bush-image-taken-in-the-masai-mara-kenya-image360636789.html
https://www.alamy.com/stock-photo-masai-giraffe-with-its-young-on-the-masai-mara-40092512.html
https://www.alamy.com/newborn-baby-giraffe-takes-its-first-steps-on-wobbly-legs-image-taken-in-the-masai-mara-kenya-image360610375.html
scroll to the third photo in https://a-z-animals.com/blog/baby-giraffe-9-pictures-and-facts/

Giraffa camelopardalis rothschildi

https://www.dreamstime.com/stock-photo-female-giraffe-baby-savannah-kenya-tanzania-east-africa-excellent-illustration-image78931408
https://www.alamy.com/rothschilds-giraffe-image8486953.html
https://www.alamy.com/west-palm-beach-floridaloxahatcheelion-country-safaridrive-throughwild-animalsafrican-giraffegiraffa-camelopandalismother-momparent-parentsad-image367695850.html
https://www.liverpoolecho.co.uk/incoming/gallery/pictures-zahra-two-week-old-baby-rothschild-8393223

A pedal flag seems to be fully developed in infants of Giraffa tippelskirchi, and more obviously precocial than the other flags. In the case of Giraffa camelopardalis there is ambivalence, because the lower legs do not seem as pale in infants as in adults.

An ilial flag is restricted to Giraffa giraffa giraffa and seldom clearly shown in photos. However, the following suggests its presence in at least some individual infants: https://www.inaturalist.org/observations/19113374.

In summary: in giraffes, the colouration of infants is so precocial that all the flags seem at least nominally present. There is scant evidence that infants rely on camouflage any more than adults do.

Publicado por milewski milewski, 16 de diciembre de 2021

Comentarios

The following shows how effective the camouflage-colouration can be when mother and infant simply stand still with none of the flags visible or activated: https://www.inaturalist.org/observations/25893289.

Publicado por milewski hace 8 meses (Marca)

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