10.5061/DRYAD.DBRV15DXZ
Frýdlová, Petra
0000-0001-9385-9743
Faculty of 1000
Mrzílková, Jana
Department of Anatomy, Third Faculty of Medicine
Šeremeta, Martin
Department of Anatomy, Third Faculty of Medicine
Křemen, Jan
Department of Anatomy, Third Faculty of Medicine
Dudák, Jan
Czech Technical University in Prague
Žemlička, Jan
Czech Technical University in Prague
Minnich, Bernd
0000-0003-1218-1913
University of Salzburg
Kverková, Kristina
Charles University
Němec, Pavel
Charles University
Zach, Petr
0000-0003-1941-2972
Department of Anatomy, Third Faculty of Medicine
Frynta, Daniel
Charles University
Determinate growth is predominant and likely ancestral in squamate reptiles
Dryad
dataset
2020
FOS: Biological sciences
determinate growth
endothermy
indeterminate growth
growth plate cartilage
Micro-CT
Squamata
European Commission
https://ror.org/00k4n6c32
CZ.02.1.01/0.0/0.0/16_019/0000766
Czech Science Foundation
https://ror.org/01pv73b02
18-15020S
Charles University Research Centre Program*
204069
Charles University Research Centre Program
204069
2020-12-14T00:00:00Z
2020-12-14T00:00:00Z
en
5681903079 bytes
43
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Body growth is typically thought to be indeterminate in ectothermic
vertebrates. Indeed, until recently, this growth pattern was considered to
be ubiquitous in ectotherms. Our recent observations of a complete growth
plate cartilage (GPC) resorption, a reliable indicator of arrested
skeletal growth, in many species of lizards clearly reject the ubiquity of
indeterminate growth in reptiles and raise the question about the
ancestral state of the growth pattern. Using X-ray micro-computed
tomography (µCT), here we examined GPCs of long bones in three basally
branching clades of squamate reptiles, namely in Gekkota, Scincoidea, and
Lacertoidea. A complete loss of GPC, indicating skeletal growth arrest,
was the predominant finding. Using a dataset of 164 species representing
all major clades of lizards and the tuataras, we traced the evolution of
determinate growth on the phylogenetic tree of Lepidosauria. The
reconstruction of character states suggests that determinate growth is
ancestral for the squamate reptiles (Squamata) and remains common in the
majority of lizard lineages, while extended (potentially indeterminate)
adult growth evolved several times within squamates. Although
traditionally associated with endotherms, determinate growth is coupled
with ectothermy in this lineage. These findings combined with existing
literature suggest that determinate growth predominates in both extant and
extinct amniotes.
We analyzed 194 femoral bones from lizards belonging to three clades of
Squamata (Gekkota, Scincoidea, and Lacertoidea). We analyzed the growth
plate cartilage (GPC) in the proximal part of the femur. We employed X-ray
micro-computed tomography (µCT) and micro-radiography (µRTG) for
vizualization of GPC. We scored the GPC state in a binary fashion, as
either present (1) or absent (0). Ancestral state reconstruction was
performed in R using the Hidden State Speciation and Extinction (HiSSE)
model implemented in the R package hisse. Additionally, we performed the
ancestral states reconstruction using maximum parsimony, as implemented in
the R package castor. The reconstructed states were plotted using the R
package phytools.