Adaptive colouration in the largest living cervid, the moose (Alces alces)

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At first sight, Alces alces seems nondescript in colouration ( and

Valerius Geist, on pages 229-232 in Grzimek's Animal Life Encyclopedia (, exaggerates somewhat when he states:
"European moose are dark brown with white legs, and American moose are black with a light saddle patch on the back, light-brown legs, and facial markings that vary between the sexes. In the female the face and nose are red-brown, while the bull has a black nose".

The following verify that the face tends to be paler than the neck and torso, in females of A. alces in North America ( and and and to some degree also in Europe ( and

However, the difference in tone between the face and the rest of the figure is noticeable only in A. a. americana (see details in comment below, titled FACIAL FLAG IN ALCES ALCES AMERICANA).

Sexual differences in the colouration of the pelage of A. alces, beyond the face, are remarkably limited ( and and and,vid:YvNAJLygu9w,st:0). Even in the case of the face, males retain the female colouration as long as the antlers are still in velvet (

Infants, although noticeably paler than adults, have colouration so plain that it, too, is nondescript (

Seasonal changes in colouration are limited. There is a single annual molt ( and and and in spring/early summer. The pelage, after being worn and weathered for a year, fades somewhat (

However, the pelage remains dark enough in winter to be conspicuous against snowy backgrounds, even at distance ( and

Despite the initial nondescript impression, my close scrutiny has revealed several noteworthy patterns of colouration, which deserve names, in A alces.

For example, the following shows a fibular flag, anterior auricular semet, and buccal semet in an adolescent female individual in the spring season, in Alces alces gigas:

Although these features are subtle, individually variable, and perhaps seasonally variable, most of them occur in most of the nine subspecies.


The antlers of A. alces, borne seasonally by males, tend to be conspicuously pale on the upper (dorsal) surface, in the subspecies with the largest antlers (

The cornual flag is derived essentially from the natural paleness of dry bone (

However, in A. a. gigas and presumably A. a. buturlini,

This makes the antlers conspicuous, even at distance (

The cornual flag in A. gigas

Cornual flag in Alces alces gigas:
scroll in

Cornual flag in Alces alces andersoni:

Possible cornual flag in Alces alces shirasi: and

Possible cornual flag in Alces alces americana:

Incipient cornual flag in Alces alces alces:


Please see

The fibular flag is best-developed in the nominate subspecies, A. a. alces, of Europe and western Russia, in which it tends to extend to the inner surface of the buttock ( and/or the hock.

The role of sheen deserves investigation.

The following shows the extreme development of the pale pelage in A. alces, in which it encompasses most of the hindleg (


A case can be made that A. alces possesses a pedal flag, in some individuals. This applies particularly to the nominate A. a. alces ( and

This pedal flag consists of conspicuous pale on the hocks and carpals (particularly on the posterior surface of the carpals), extending to varying extent down the lower limbs towards the hooves, and connected to the fibular flag where the latter is present (

The fetlocks and pasterns themselves are not whitish ( and and and and and, except in some individuals of the nominate A. a. alces (

A factor undermining the validity of a pedal flag in A. alces is that, for much of the year, the pale on the legs is inconspicuous against a background of snow ( and

To the degree that the pedal flag is valid in A. alces, it is linked to, and subsidiary to, the fibular flag ( In A. a. alces, the joint pattern can perhaps be called a pedofibular flag.


Please see

One of the most consistent patterns of colouration in A. alces is a small-scale dark/pale contrast on the anterior base of the ear pinna (

The location of this pattern is such that it accentuates the movements of the ears, in vigilance and emotional expression. Such accentuation is hypothetically adaptive in social (intraspecific) interactions, and may additionally function in anti-predator, defensive displays.

Several other genera of cervids possess auricular semets. However, that of A. alces is restricted to the anterior surface, and has its own particular configuration.

The following show the anterior auricular semet in various subspecies of A. alces:

A. a. alces:

A. a. americana:

A. a. gigas:

A. a. andersoni:

A. a. shirasi:

In Alces alces, unlike another large cervid partly sympatric with it, the auricular semet does not disappear in mature males (see

The following show that the anterior auricular semet, although absent in newborns, develops before the infantile colouration is lost, and before the muzzle develops:


The peculiar muzzle of A. alces is so distracting that the colouration around the mouth may go unnoticed. Furthermore, this colouration is subtle and individually variable.

However, there tends to be a pattern in which the broadly dark lower lip is offset by pale ventral to the gape. The clearest illustration is

The following are additional illustrations: and and and and scroll to second photo in and and and and and and

This pattern of colouration hypothetically accentuates the chewing movements ( This hypothetically aids vigilance during rumination, when two or more adult/adolescent individuals rest within sight of each other (

Buccal semet in Alces alces buturlini:

Buccal semet in Alces alces gigas:

Variation in this feature deserves further investigation. The pattern seems clearest in spring, when the worn, weathered pelage has faded but the dark on the lower lip has not faded ( The following shows the minimal expression of the buccal semet (, but it is unclear whether this is because of the summer season or individual variation.

Of all the features described here, the buccal semet is the most precocial, in the sense that the lower lip is dark even in infants ( and and

Publicado el septiembre 19, 2023 12:46 MAÑANA por milewski milewski


Fibular flag and anterior auricular semet in Alces alces shirasi:

Publicado por milewski hace 10 meses

The withers tend to be pale, offset by the darkness of the short mane ( and and and

However, this pattern is never graphic enough, in any subspecies/individual, to warrant a name. Furthermore, it is disrupted by the weathering, fading, and molt of the pelage, more than any other aspect of colouration (

It is perhaps surprising that the dewlap of Alces alces lacks conspicuous colouration (

Publicado por milewski hace 10 meses
Publicado por milewski hace 10 meses

Weren't the American subspecies recognised as a separate species a while back?

Publicado por paradoxornithidae hace 10 meses


Valerius Geist regarded Alces as consisting of two 'types', one of which occurs in North America plus eastern Asia - intriguingly including the small form, cameloides, of Manchuria ( and Ussuri (

Publicado por milewski hace 10 meses

Very interesting!

Publicado por beartracker hace 10 meses

The following series of photos of Alces alces in trotting gait show the variation in colouration in the inner (medial) and outer (lateral) surfaces of the legs:

Publicado por milewski hace 10 meses

@paradoxornithidae @matthewinabinett


In Alces alces americana of eastern North America, the face tends to be so much paler than the neck and body that this may be an adaptively conspicuous feature.

The process producing this pattern is that the face remains the same colour from birth to adulthood (

Adult females:

Adult males in velvet:

In adult males in hard antler, the rostrum turns dark:

The paleness of the face in A. a. americana does not detract from the validity of the anterior auricular flag:

The facial flag does not categorically distinguish subspecies americana, because even in the far west of Russia some individuals (of the nominate subspecies, alces) show similar colouration (

Publicado por milewski hace 10 meses

Adult female of Alces alces americana in autumn:

Alces alces americana at the stage when the infantile colouration is lost:

Publicado por milewski hace 10 meses
Publicado por milewski hace 10 meses


The following individual of Alces alces shirasi is an exception to the rule that the pelage of the rostrum of the face turns dark once the antlers turn hard, each year:

The following is a converse exception, in which the rostrum is already dark, despite the antlers still being in velvet:

The following shows that the rostrum remains dark after the antlers are shed, in winter:

Publicado por milewski hace 10 meses
Publicado por milewski hace 10 meses

Buccal semet in Taurotragus oryx, which shares the name 'eland' with Alces alces:

Publicado por milewski hace 10 meses

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