'Mustelidae' or 'Mustelids' (from Latin ''mustela'',
weasel), commonly referred to as the 'weasel family', is a family of
carnivorous mammals. The Mustelidae is a diverse family and the largest in the order Carnivora, at least partly because it has in the past been a catch-all category for many early or poorly differentiated
taxa.
[1]
Variety
The Mustelidae in general are
phylogenetically relatively primitive and so were difficult to classify until genetic evidence started to become available. The increasing availability of such evidence may well result in some members of the family being moved to their own separate families, as has already happened with the
skunks, previously considered to be members of the mustelid family.
Mustelids vary greatly in size and behavior. The
least weasel is not much larger than a mouse. The
giant otter can weigh up to 76 lb (34 kg). The
wolverine can crush bones as thick as the femur of a
moose to get at the marrow, and has been seen attempting to drive
bears from kills. the
sea otter uses rocks to break open shellfish to eat. The
marten is largely
arboreal, while the
badger digs extensive networks of tunnels, called
setts. Some mustelids have been domesticated. The
ferret and the
tayra are kept as pets, or as working animals for hunting or vermin control. Others have been important in the
fur trade. The
mink is often
raised for its fur.
As well as one of the most species-rich families in the order
Carnivora, mustelidae is one of the oldest. Mustelid-like forms first appeared about 40 million years ago, roughly coinciding with the appearance of
rodents. The direct ancestors of the modern mustelids first appeared about 15 million years ago.
Characteristics
Within a large range of variation, the mustelids exhibit some common characteristics.
They are typically small animals with short legs, short round ears, and thick fur. Some mustelids have exquisite furs which have been valuable for many centuries—the mink, the
sable (a type of marten) and the ermine (stoat) are all members of the family. This has led to the hunting of these animals, especially in the past. One species, the
sea mink (Mustela macrodon) of New England and Canada, was driven to extinction by fur trappers around the same time that the
passenger pigeon was declining. Its appearance and habits are almost unknown today because no complete specimens can be found and no systematic contemporary studies were conducted. Today some mustelids are in trouble for other reasons. The sea otter, that almost shared the fate of the sea mink, now risks being destroyed by oil spills and the side effects of overfishing; the
black-footed ferret, a relative of the
European polecat, suffers from the disappearance of the American
prairie; and the
wolverine is in a long, slow decline because of habitat destruction and persecution.
Most mustelids are solitary, nocturnal animals, and are active year-round.
Mustelids have
anal scent glands that produce a strong-smelling secretion the animals use for sexual signaling and for marking territory. The most developed of these scent glands are found in skunks (''Mephitinae''), which were moved into a new family,
Mephitidae, following a convincing paper (
Dragoo and Honeycutt, 1997, Journal of Mammalogy, 78(2): 426-443), that somewhat reorganized these two families based on
DNA analyses.
Most mustelid reproduction involves
embryonic diapause. The
embryo does not immediately implant in the
uterus, but remains dormant for a period of time. No development takes place as long as the embryo remains unattached to the uterine lining. As a result, the normal gestation period is extended, sometimes up to a year. This allows the young to be born under more favorable environmental conditions. Reproduction has a large energy cost and it is to a female's benefit to have available food and mild weather. The young are more likely to survive if birth occurs after previous offspring have been weaned.
Ecology
Several members of the family are aquatic to varying degrees, ranging from the semi-aquatic mink, the river otters, and the highly aquatic
sea otter. The sea otter is also the only non-primate mammal known to use a tool while foraging. It uses "anvil" stones to crack open the shellfish that form a significant part of its diet. It is a "
keystone species," keeping its prey populations in balance so some do not outcompete the others and they do not destroy the
kelp in which they live.
The
black-footed ferret is entirely dependent on the another keystone species, the
prairie dog. A family of four ferrets will eat 250 prairie dogs in a year. The ferrets require a prairie dog colony of 500 acres to maintain a stable population to support their predation.
The
Mongoose and the
meerkat bear a striking resemblance to many mustelids but belong to a distinctly different
suborder - the
Feliformia (all those carnivores sharing more recent origins with the
Felidae) and not the
Caniformia (those sharing more recent origins with the
Canidae). Because the mongoose and the mustelids occupy similar
ecological niches,
convergent evolution has led to some similarity in form and behavior.
[2]
Family
;'FAMILY MUSTELIDAE' (55 species in 24 genera)
★ 'Subfamily Lutrinae' (
Otters)
★
★ Genus ''
Amblonyx''
★
★ Genus ''
Aonyx''
★
★ Genus ''
Enhydra'' (
Sea Otter)
★
★ Genus ''
Lontra'' (American River and
Marine Otters)
★
★ Genus ''
Lutra'' (includes
European Otter)
★
★ Genus ''
Hydrictis''
★
★ Genus ''
Lutrogale''
★
★ Genus ''
Pteronura'' (
Giant Otter)
★ 'Subfamily Melinae' (
Badgers)
★
★ Genus ''
Arctonyx'' (
Hog Badger)
★
★ Genus ''
Meles'' (
Eurasian Badger)
★
★ Genus ''
Melogale'' (
Ferret Badgers)
★
★ Genus ''
Mydaus'' (
Stink Badgers - considered by some authorities to be part of
Mephitidae)
★ 'Subfamily Mellivorinae' (
Ratels or Honey Badgers)
★
★ Genus ''
Mellivora''
★ 'Subfamily Taxideinae' (
American Badgers)
★
★ Genus ''
Taxidea'' (
American Badger)
★
★ Genus ''
Chamitataxus'' (Extinct)
★ 'Subfamily
Mustelinae'
★
★ Genus ''
Eira'' (
Tayra)
★
★ Genus ''
Ekorus'' (Extinct)
★
★ Genus ''
Galictis'' (
Grisón)
★
★ Genus ''
Gulo'' (
Wolverine)
★
★ Genus ''
Ictonyx'' (
Striped Polecat)
★
★ Genus ''
Lyncodon'' (
Patagonian Weasel)
★
★ Genus ''
Martes'' (
Sable and
Martens)
★
★ Genus ''
Mustela'' - (
Weasels,
Ferrets,
Mink and
Stoats)
★
★ Genus ''
Poecilogale'' (
African Striped Weasel)
★
★ Genus ''
Vormela'' (
Marbled Polecat)
See also
★
Embryonic diapause
References
1. A Skunk By Any Other Name…
2. Online Biology Glossary
★