Mole (animal)

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This article is about mammals called "moles". For other uses, see Mole (disambiguation).
Not to be confused with Vole.
Moles
Talpa europaea MHNT.jpg
European Mole
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Infraclass: Eutheria
Order: Soricomorpha
Family: Talpidae
in part
Genera

12 genera, see text

Moles are small mammals adapted to a subterranean lifestyle. They have cylindrical bodies, velvety fur, very small, difficult to see ears and eyes,[1] reduced hindlimbs and short, powerful forelimbs with large paws adapted for digging. The term "mole" is especially and most properly used for "true moles" of the Talpidae family in the order Soricomorpha found in most parts of North America,[2] Asia, and Europe although may refer to other completely unrelated mammals of Australia and southern Africa which have also evolved the mole body plan; it is not commonly used for some talpids, such as desmans and shrew-moles, which do not quite fit the common definition of "mole".

Terminology[edit]

By the era of Early Modern English, the mole was also known in English as mouldywarp, a word having cognates in other Germanic languages such as German (Maulwurf),[3] and Danish, Norwegian, Swedish and Icelandic (muldvarp, mullvad, moldvarpa), where the muld/mull/mold part of the word means soil and the varp/vad/varpa part means throw, hence "one who throws soil" or "dirt tosser".

Male moles are called "boars", females are called "sows". A group of moles is called a "labour".[4]

Characteristics[edit]

Breathing underground[edit]

Moles have been found to tolerate higher levels of carbon dioxide than other mammals, because their blood cells have a special and unique haemoglobin protein. Moles are able to reuse the oxygen inhaled when above ground, and as a result, are able to survive in low-oxygen environments such as underground burrows.[5]

Extra thumb[edit]

Mole paw

Moles have polydactyl forepaws; each has an extra thumb (also known as a prepollex) next to the regular thumb. While the mole's other digits have multiple joints, the prepollex has a single, sickle-shaped bone which develops later and differently from the other fingers during embryogenesis from a transformed sesamoid bone in the wrist, independently evolved but similar to the giant panda thumb. This supernumerary digit is species-specific, as it is not present in shrews, the mole's closest relatives. Androgenic steroids are known to affect the growth and formation of bones, and a connection is possible between this species-specific trait and the "male" genitals apparatus in female moles of many mole species (gonads with testicular and ovary tissues). [6]

Diet[edit]

A mole's diet primarily consists of earthworms and other small invertebrates found in the soil, and a variety of nuts. The mole runs are in reality 'worm traps', the mole sensing when a worm falls into the tunnel and quickly running along to kill and eat it.[7] Because their saliva contains a toxin that can paralyze earthworms, moles are able to store their still-living prey for later consumption. They construct special underground "larders" for just this purpose; researchers have discovered such larders with over a thousand earthworms in them. Before eating earthworms, moles pull them between their squeezed paws to force the collected earth and dirt out of the worm's gut.[8]

The star-nosed mole can detect, catch and eat food faster than the human eye can follow. [9]

Breeding[edit]

Breeding season for a mole depends on species but is generally February through May. Males search for females by letting out high-pitched squeals and tunneling through foreign areas.

The gestation period of the Eastern (US) mole (Scalopus aquaticus) is approximately 42 days. Three to five young are born, mainly in March and early April.[10]

Townsend moles mate in February and March, and the 2–4 young are born in March and April after a gestation period of about 1 month.[11] The Townsend mole is endangered in the United States and Canada.[12]

Coast moles produce a litter of 2–5 pups between March and April.[12]

Pups leave the nest 30–45 days after birth to find territories of their own.

Social structure[edit]

Moles are solitary creatures, coming together only to mate. Territories may overlap, but moles avoid each other and males may fight fiercely if they meet.

Classification[edit]

The family Talpidae contains all the true moles and some of their close relatives. Desmans, which are Talpidae but are not normally called "moles", are not shown below, but belong to the subfamily Talpinae (note the slightly different name). Those species called "shrew moles" represent an intermediate form between the moles and their shrew ancestors, and as such may not be fully described by the article.

On the other hand, there is no monophyletic relation between the mole and the hedgehog, both of which were previously placed in the now abandoned order Insectivora. As a result, Soricomorpha ("shrew-like animals" including moles), previously within Insectivora, has been elevated to the level of an order. [13]

Other "moles"[edit]

While many groups of burrowing animals (pink fairy armadillos, tuco-tucos, mole rats, mole crickets and mole crabs) have developed close physical similarities with moles due to convergent evolution, two of these are so similar to true moles, they are commonly called and thought of as "moles" in common English, although they are completely unrelated to true moles or to each other. These are the golden moles of southern Africa and the marsupial moles of Australia. While difficult to distinguish from each other, they are most easily distinguished from true moles by shovel-like patches on their noses which they use in tandem with their abbreviated forepaws to swim through sandy soils.

The golden moles[edit]

A golden mole

The golden moles belong to the same branch on the tree of life as the tenrecs, called Tenrecomorpha or Afrosoricida, which in turn stem from a main branch of placental mammals called the Afrosoricida. This means they share a closer common ancestor with such existing afrosoricids as elephants, manatees, and aardvarks than they do with other placental mammals such as true Talpidae moles.

Marsupial moles[edit]

A marsupial mole

As marsupials, these moles are even more distantly related to true Talpidae moles than golden moles, both of which belong to the eutheria, or placental mammals. This means they are more closely related to such existing Australian marsupials as kangaroos or koalas, and even to a lesser extent to American marsupials, such as opossums than they are to placental mammals such as golden or Talpidae moles.

Class Mammalia

Interaction with humans[edit]

Pelts[edit]

Advertisement in Illustrated Sporting and Dramatic News, 1921

Moles' pelts have a velvety texture not found in surface animals. Surface-dwelling animals tend to have longer fur with a natural tendency for the nap to lie in a particular direction, but to facilitate their burrowing lifestyle, mole pelts are short and very dense and have no particular direction to the nap. This makes it easy for moles to move backwards underground, as their fur is not "brushed the wrong way". The leather is extremely soft and supple. Queen Alexandra, the wife of Edward VII of the United Kingdom, ordered a mole-fur garment to start a fashion that would create a demand for mole fur, thereby turning what had been a serious pest problem in Scotland into a lucrative industry for the country. Hundreds of pelts are cut into rectangles and sewn together to make a coat. The natural color is taupe, but it is readily dyed any color.[14]

Pest status[edit]

Molehills in eastern Bohemia

Moles are considered to be agricultural pests in some countries, while in others, such as Germany, they are a protected species, but may be killed if a permit is received. Problems cited as caused by moles include contamination of silage with soil particles, making it unpalatable to livestock, the covering of pasture with fresh soil reducing its size and yield, damage to agricultural machinery by the exposure of stones, damage to young plants through disturbance of the soil, weed invasion of pasture through exposure of freshly tilled soil, and damage to drainage systems and watercourses. Other species such as weasels and voles may use mole tunnels to gain access to enclosed areas or plant roots.

Moles burrow lawns, raising molehills, and killing the lawn, for which they are sometimes considered pests. They can undermine plant roots, indirectly causing damage or death. Moles do not eat plant roots.[15]

A mole trap

Moles are controlled with traps such as mole-catchers, smoke bombs, and poisons such as calcium carbide. Strychnine was also used for this purpose in the past. The most common method now is Phostoxin or Talunex tablets. They contain aluminium phosphide and are inserted in the mole tunnels, where they turn into phosphine gas (not be confused with phosgene gas). More recently, high-grade nitrogen gas has proven effective at killing moles, with the added advantage of having no polluting effect to the environment. [15]

Other common defensive measures include cat litter and blood meal, to repel the mole, or flooding or smoking its burrow. Devices are also sold to trap the mole in its burrow, when one sees the "mole hill" moving and therefore knows where the animal is, and then stabbing it. Humane traps which capture the mole alive so it may be transported elsewhere are also options.[15]

However, in many gardens, the damage caused by moles to lawns is mostly visual, and it is also possible to simply remove the earth of the molehills as they appear, leaving their permanent galleries for the moles to continue their existence underground.[15]However, when the tunnels are near the surface, they collapse when the ground is soft after heavy rain and leave unsightly furrows in the lawn.

Meat[edit]

Although the mole can be eaten, the taste is said to be deeply unpleasant.[16]

See also[edit]

References[edit]

  1. ^ Kott, Ondřej; Sumbera, Radim; Nemec, Pavel (2010). Iwaniuk, Andrew, ed. "Light Perception in Two Strictly Subterranean Rodents: Life in the Dark or Blue?". PLoS ONE 5 (7): e11810. doi:10.1371/journal.pone.0011810. PMC 2911378. PMID 20676369. 
  2. ^ Kevin Campbell. "Mole Distribution Maps". University of Manitoba. Retrieved 2010-03-11. 
  3. ^ Rackham, Oliver, The Illustrated History Of The Countryside page 130 (quoting J. Seddon, The boke of surveying and improvments – [sic]) ISBN 0-297-84335-4
  4. ^ "Moles". animalcorner.co.uk. 
  5. ^ "Secret of how moles breathe underground revealed". The Telegraph. 20 July 2010. 
  6. ^ "How the mole got its twelve fingers". University of Zurich. 12 July 2011. Retrieved July 2011. 
  7. ^ Moles. Pest-management.co.uk. Retrieved on 2012-05-12.
  8. ^ The Life of Mammals, David Attenborough, 2002
  9. ^ Salisbury, David F. (February 2005). "Marsh-dwelling mole gives new meaning to the term 'fast food'". EurekAlert. Retrieved July 2011. 
  10. ^ "Moles their biology and control". Icwdm.org. Retrieved 2013-10-10. 
  11. ^ Scapanus townsendii. California Department of Fish and Game
  12. ^ a b "Coast Mole Control and Trapping". Animalcontrolsolutions.com. Retrieved 2013-10-10. 
  13. ^ Mouchaty, Suzette K.; Gullberg, Anette; Janke, Axel; Arnason, Ulfur (2000). "The Phylogenetic Position of the Talpidae Within Eutheria Based on Analysis of Complete Mitochondrial Sequences". Mol Biol Evol 17 (1): 60–67. doi:10.1093/oxfordjournals.molbev.a026238. PMID 10666706. 
  14. ^ "Furs types in brief". furcommission.com. Archived from the original on 2011-07-21. Retrieved 6 October 2010. 
  15. ^ a b c d "How to get rid of moles". Extermine.com. 2004. Retrieved July 2011. 
  16. ^ Howard, Martin (2010-04-01). "Why we need eccentricity". The Guardian (London). Retrieved 2010-05-13. 

External links[edit]