What does a high intermembral index mean?
Chimpanzees have an intermembral index of 10612, meaning that their forelimbs are longer than their hindlimbs. A high intermembral index in chimpanzees reflects the fact that they rely heavily on their forelimbs for climbing and arm-hanging/swinging activities.
What does the intermembral index describe?
The intermembral index is a ratio used to compare limb proportions, expressed as a percentage. It is equal to the length of forelimbs (humerus plus radius) divided by the length of the hind limbs (femur plus tibia) multiplied by 100, otherwise written mathematically as: (en)
What does an intermembral index indicate if it is close to 100?
being strictly quantitative, is the intermembral index. Briefly, the index is a ratio expressed as percentage of arm length to leg length; an index over 100 indicates relatively long arms.
What does the intermembral index reflect?
This index expresses total length of humerus plus radius as percentage of total length of femur plus tibia. Thus, the index is low in primates with long hind legs, cluster variously near 100 in quadrupeds, and exceed 100 considerably in primates that frequently use their forearms as means of locomotion.
What does a low intermembral index mean?
The intermembral index is used frequently in primatology, since it helps predict primate locomotor patterns. For scores lower than 100, the forelimbs are shorter than the hind limbs, which is common in leaping primates and bipedal hominids.
What is the intermembral index of a baboon?
Baboons
| Common name | Species | Intermembral index |
|---|---|---|
| Yellow baboon | P. cynocephalus | 96 |
| Hamadryas baboons | P. hamadryas | 95 |
| Kinda baboon | P. kindae | – |
What is the intermembral index of the mandrill?
95
Mandrills and Drills
| Common name | Species | Intermembral index |
|---|---|---|
| Mandrill | Mandrillus sphinx | 95 |
| Drill | M. leucophaeus | – |
Why is intermembral index a useful measurement when considering an animal locomotion?
What is a gibbons intermembral index?
Intermembral index = (humerus length + radius length) x 100 / (femur length + tibia length); Abbreviations: Ce=Cercopithecinae, Co=Colobinae, H=Hominoidea. Homo. H. 72. Chlorocebus.
What is the intermembral index of a tarsier?
Family TARSIIDAE
| Common name | Species | Intermembral index |
|---|---|---|
| Western tarsier | Cephalopachus bancanus | 52 |
| Dian’s tarsier | Tarsius dentatus | – |
| Makassar tarsier | T. fuscus | – |
What is the intermembral index?
The intermembral index is a ratio used to compare limb proportions, expressed as a percentage. It is equal to the length of forelimbs ( humerus plus radius) divided by the length of the hind limbs ( femur plus tibia) multiplied by 100, otherwise written mathematically as:
How do you calculate the intermembral index of a bone?
All indices are based on measurements of the maximum length of the long bones. Intermembral index = [ (humerus + radius) × 100]/ (femur + tibia); Humerofemoral index = (humerus × 100)/femur.
What is the intermembral index of a snow leopard?
The intermembral index is only 84.7% and falls within values for other large cats. The snow leopard’s hunting behavior has been recorded on film in recent years and indicates that from an ambush it can display rapid acceleration and pursuit of bovid prey, with long leaps and sharp turns.
What is the humeroradial and intermembral index of a cheetah?
The humeroradial index (94.6%) is only slightly less than that of the lion (98.3%) and the cheetah (103.3%), while the femorotibial index (105%) matches that of the cheetah, indicating longer lower limbs for a longer stride and potentially higher running speeds. The intermembral index is only 84.7% and falls within values for other large cats.