Patterns of growth in monitor lizards (Varanidae) as revealed by computed tomography of femoral growth plates

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F17%3A10359240" target="_blank" >RIV/00216208:11310/17:10359240 - isvavai.cz</a>

Result on the web

<a href="http://dx.doi.org/10.1007/s00435-016-0338-3" target="_blank" >http://dx.doi.org/10.1007/s00435-016-0338-3</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1007/s00435-016-0338-3" target="_blank" >10.1007/s00435-016-0338-3</a>

Result language

angličtina

Original language name

Patterns of growth in monitor lizards (Varanidae) as revealed by computed tomography of femoral growth plates

Original language description

Growth plate cartilage (GPC) is responsible for the growth of long bones due to endochondral ossification, which is the main mechanism of longitudinal skeletal growth in tetrapods. Degradation of GPC is a sign of determinate growth as it arrests the growth irreversibly. By contrast, indeterminate growth requires the persistence of GPC throughout the entire life. Monitor lizards (Varanidae) were previously reported to exhibit a dual type of growth, determinate as well as indeterminate. To reinvestigate this highly unexpected finding, we examined 13 species of varanids and their close relatives (Shinisauridae and Helodermatidae). In order to visualize GPC on the proximal part of the femur, we employed micro-radiography and micro-computed tomography. In large-bodied species, an extended capability of longitudinal growth was demonstrated; GPC was preserved for most of their lives. On the other hand, GPC senescence with complete disappearance of cartilage was found in adults of small-bodied varanids. These results confirm previous finding and, together with the absence of GPC in the outgroup species, challenge the universality of indeterminate growth in squamates. Moreover, we observed disappearance of GPC in an extremely old Varanus indicus, implying that GPC degradation is not entirely absent but only delayed to senescence in this large-bodied species. These findings raise the intriguing possibility that it is the timing, rather than other underlying mechanisms, what sets apart determinate from indeterminate growth. We therefore suggest that this dual type of growth represents an extreme case of heterochrony and is a consequence of strong sexual selection pressure to large-bodied varanids.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10613 - Zoology

Project

—

Continuities

S - Specificky vyzkum na vysokych skolach<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2017

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Zoomorphology

ISSN

0720-213X

e-ISSN

—

Volume of the periodical

136

Issue of the periodical within the volume

1

Country of publishing house

DE - GERMANY

Number of pages

12

Pages from-to

95-106

UT code for WoS article

000396049100008

EID of the result in the Scopus database

2-s2.0-85006851006