176
W. R. Jackman and Y. Gibert
Abbreviations
Aldh1a Aaldehyde dehydrogenase 1a
AP
Anteroposterior
CB5
Fifth ceratobranchial (cartilage/bone)
CNC
Cranial neural crest
CRABP Cellular retinoic acid binding protein
Cyp26 Cytochrome P450 26
DEAB N,N-diethylaminobenzaldehyde
Dll
Distal-less
dpf
Days post fertilization
EGF
Epidermal growth factor
FGF
Fibroblast growth factor
hpf
Hours post fertilization
RA
Retinoic acid
RAR
Retinoic acid receptor
Shh
Sonic hedgehog
VA
Vitamin A
Introduction
If the ichthyologist have reason to complain of the monotony which unavoidably pervades his
descriptions of the external characters of the objects of his study, the anatomist in treating of
the dental system of fishes, finds, on the contrary, his difficulty in obtaining the command of
language sufficiently varied to pourtray the singular diversity and beauty, and the interesting
physiological relations which are manifested in that part of their organization. (Owen 1840)
Richard Owen, the preeminent mid-nineteenth century English comparative morphologist, wrote the above in response to an earlier complaint by the French anatomist
Bernard Germain de Lacépède lamenting the monotony of the external form of fish
(Cuvier 1819). Considering the vast diversity of external form now appreciated in
actinopterygians, it is perhaps difficult to understand Lacépède’s position. This was
certainly true for Owen in 1840, who had just spent an enormous effort cataloging
the diversity of vertebrate dentition from cartilaginous fishes to mammals in his work
Odontography (Owen 1840). In it, he details a treasure-trove of tooth morphological
variation: myriad forms that make it fascinating to consider how they may have come
to exist (Fig. 7.1).
Owen would perhaps have looked to a divine explanation for this tremendous
dental diversity in vertebrates, having been a vehement detractor of the theory of
evolution by natural selection. However, today the issue of tooth origins can be
framed by two overarching questions: how did the diversity of location, number, and
form of teeth arise in the evolution of vertebrates and how does the dentition form
W. R. Jackman and Y. Gibert
Abbreviations
Aldh1a Aaldehyde dehydrogenase 1a
AP
Anteroposterior
CB5
Fifth ceratobranchial (cartilage/bone)
CNC
Cranial neural crest
CRABP Cellular retinoic acid binding protein
Cyp26 Cytochrome P450 26
DEAB N,N-diethylaminobenzaldehyde
Dll
Distal-less
dpf
Days post fertilization
EGF
Epidermal growth factor
FGF
Fibroblast growth factor
hpf
Hours post fertilization
RA
Retinoic acid
RAR
Retinoic acid receptor
Shh
Sonic hedgehog
VA
Vitamin A
Introduction
If the ichthyologist have reason to complain of the monotony which unavoidably pervades his
descriptions of the external characters of the objects of his study, the anatomist in treating of
the dental system of fishes, finds, on the contrary, his difficulty in obtaining the command of
language sufficiently varied to pourtray the singular diversity and beauty, and the interesting
physiological relations which are manifested in that part of their organization. (Owen 1840)
Richard Owen, the preeminent mid-nineteenth century English comparative morphologist, wrote the above in response to an earlier complaint by the French anatomist
Bernard Germain de Lacépède lamenting the monotony of the external form of fish
(Cuvier 1819). Considering the vast diversity of external form now appreciated in
actinopterygians, it is perhaps difficult to understand Lacépède’s position. This was
certainly true for Owen in 1840, who had just spent an enormous effort cataloging
the diversity of vertebrate dentition from cartilaginous fishes to mammals in his work
Odontography (Owen 1840). In it, he details a treasure-trove of tooth morphological
variation: myriad forms that make it fascinating to consider how they may have come
to exist (Fig. 7.1).
Owen would perhaps have looked to a divine explanation for this tremendous
dental diversity in vertebrates, having been a vehement detractor of the theory of
evolution by natural selection. However, today the issue of tooth origins can be
framed by two overarching questions: how did the diversity of location, number, and
form of teeth arise in the evolution of vertebrates and how does the dentition form