A compendium of the biological peculiarities of the roan antelope (Hippotragus equinus)
The roan antelope (Hippotragus equinus) seems to be the largest animal specifically adapted to mature vegetation in nutrient-poor (moist/dystrophic) savannas, worldwide.
If so, what are the various biological attributes, and ecological adaptations, that have led to this distinctive status?
In particular, how does the roan antelope differ from other ruminants, including its only extant congener, the sable antelope (Hippotragus niger)?
評論
Evidence of buccal semet
https://www.inaturalist.org/observations/194460948
Creche
https://www.alamy.com/roan-hippotragus-equinus-on-private-game-ranch-great-karoo-south-africa-image263057101.html?imageid=5F0D1A96-E1F5-4E83-9293-EBBE9BE31A2D&p=215565&pn=3&searchId=bf54820912fa8b8654b0587c83cd4188&searchtype=0
https://www.alamy.com/stock-photo-roan-antelope-hippotragus-equinus-adult-w-regional-park-w-transborder-59189738.html?imageid=66386DE1-36D7-4F8B-A3A8-783EC28B2A82&p=86574&pn=5&searchId=5ed1e1ea051df95555f6aaed35fb537c&searchtype=0
https://www.alamy.com/a-full-length-portrait-of-a-roan-antelope-hippotragus-equinus-it-is-standing-on-the-grass-field-and-looking-to-the-right-image429376366.html?imageid=DF1EADBC-4397-4AE3-9C35-1FB37771FA6B&p=224192&pn=1&searchId=d3350f0b953b17636829cec591564ee8&searchtype=0
https://www.alamy.com/a-close-up-profile-portrait-of-a-roan-antelope-hippotragus-equinus-it-shows-the-head-and-neck-together-with-large-antlers-image429376262.html?imageid=51F04DDC-EFAB-4CE4-B304-781CE27CA2CB&p=224192&pn=1&searchId=d3350f0b953b17636829cec591564ee8&searchtype=0
https://www.alamy.com/roan-antelope-hippotragus-equinus-two-males-fighting-kafue-national-image65793207.html?imageid=17439AC6-3ACB-46C4-A11E-84FD00C19D98&p=8586&pn=1&searchId=d3350f0b953b17636829cec591564ee8&searchtype=0
https://www.alamy.com/roan-antelope-hippotragus-equinus-red-biiled-oxpeckers-buphagus-erythorhynchus-on-her-shoulder-parasites-symbiosis-food-chain-botswana-africa-image398722775.html?imageid=8A924AE9-8D23-49D2-B81C-08F294CA1CBF&p=77483&pn=1&searchId=d3350f0b953b17636829cec591564ee8&searchtype=0
https://www.alamy.com/a-roan-antelope-with-her-baby-calf-by-her-side-image68685310.html?imageid=F5C3C1CB-69B5-462F-AB0C-76F98FD979FE&p=81691&pn=1&searchId=d3350f0b953b17636829cec591564ee8&searchtype=0
BODY MASS OF HIPPOTRAGUS EQUINUS EQUINUS
Reference: Pienaar U de V (1968) The use of immobilizing drugs in conservation procedures for roan antelope. Acta Zoologica et Pathologica 46: 39-51.
(Also see https://the-eis.com/elibrary/sites/default/files/downloads/literature/Developments%20in%20the%w20capture%20and%20airlift%20of%20roan%20antelope_1974.pdf and https://www.researchgate.net/publication/231961605_Saving_the_Roan_Antelope.)
Ten individuals, captured in Kruger National Park, had the following estimated ages and body masses:
FEMALES
10-12 years 204 kg
7-8 years 213 kg
6-7 years 213 kg
3 years 145 kg
1.75 years 159-181 kg
1.5 years 159 kg
1.25 years 100-113 kg
MALES
5-6 years 250-272 kg
4-5 years 218 kg
1 year 91 kg
My commentary:
Juveniles seem to reach half of mature body mass at about 1.25 years old.
Mature body mass is about 213 kg in females, and 260 kg in males.
Although the roan antelope is, overall, larger-bodied than its congener the sable antelope (Hippotragus niger), it turns out that the subspecies of the two species that occur in Kruger National Park are similar in body mass.
Furstenburg (https://www.researchgate.net/publication/316165442_Focus_on_the_Roan_AntelopeHippotragus_equinus), referring to the species as a whole rather than to the southern African subspecies, states that adult females have mean body mass >230 kg, and that this is on average 25 kg less than the mean body mass of adult males. I suspect that the disparity with Pienaar (1968) is owing to the fact that the West African subspecies is considerably heavier than H. e. equinus.
新增評論