Newts are small, usually bright-coloured semiaquatic salamanders of
North America, Europe and North
Asia.
The three common British species are the Great Crested Newt (Triturus
cristatus), Smooth Newt (Triturus vulgaris) and the Palmate Newt (Triturus helveticus).
In North America, the Red-spotted Newt (Diemictylus
viridescens) is one of the most abundant species.
In Japan, the Sword-tail
Newt (Cynops ensicauda) is becoming rare and is threatened by pollution and deforestation.
Newts have the ability to regenerate limbs, eyes and spinal cords. The cells at the site of the injury
have the ability to de-differentiate, reproduce rapidly, and differentiate again to create a new limb or organ. One theory is
that the de-differentiated cells are related to tumour cells since chemicals which
produce tumours in other animals will produce additional limbs in newts.
Newts can take several years to reach sexual maturity. It is known that their main breeding season is between February and
June.
The history of the word newt is interesting. The oldest form of the name is eft, which is still used for newly
metamorphosed juveniles, but according to the Oxford
English Dictionary it changed for unknown reasons first to euft and then to ewt. For some time then it was
an ewt, but then the N moved over and it became a newt. See A, an for
other examples.
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