From embryo to turtle cracker, a team led by paleobiologist Julia Türtscher of the University of Vienna investigated the tiger shark's repeated alterations in tooth morphology.
The discovery, which was just published in the Journal of Anatomy, is also important in the science of paleontology in deriving inferences about ancient species from the plethora of preserved shark teeth.
Multiple tooth forms complicate the study
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Cartilaginous fishes such as sharks, skates, and rays have what is known as revolver dentition, which means that when they lose a tooth, a new one grows in its place for the rest of their life.
"As a result, we have an unbelievable number of teeth from both living and fossil cartilaginous fishes that we can use to explore when and how specific species developed or died out again," explains Julia Türtscher of the University of Vienna's Department of Palaeontology, as per ScienceDaily.
A significant issue in this sort of study is that the morphology of the teeth in most shark species varies throughout the course of their lives.
The current study also gave the first detailed description of the tooth shape of tiger shark embryos.
According to this study, the embryos generate teeth in the mother's womb, albeit without serrations at first.
However, the permanent alteration of teeth begins even before birth, and the freshly created teeth reveal the first main serrations.
This suggested that the first teeth are formed in the womb and swallowed, as Türtscher explains.
The teeth of bigger animals become larger, and more main serrations are added. Secondary serrations, on the other hand, appear only when the creatures have grown to a significant size.
According to the scientist, one of the most difficult obstacles for these studies has been the occurrence of diverse tooth forms in the same jaw, which has proven to be one of the most difficult challenges for these investigations.
Although more shark species are found and reported each year, precise descriptions of tooth forms and heterodonty patterns for the majority of species are sparse or poorly documented.
This gap has finally been addressed for the tiger shark according to a study undertaken at the University of Vienna's Department of Palaeontology and published in the Journal of Anatomy at the end of April.
Tiger shark tooth forms in various sizes
Ontogenetic phases are re-evaluated and illustrated in-depth. Finally, there are several instances of
The evolution of dental characteristics in the extant tiger shark G. cuvier establishes a baseline for future morphological and genetic investigations on shark dental diversity.
As a result, it has the potential to aid in explaining the underlying developmental and behavioral issues.
The evolutionary mechanisms behind elasmobranch dental diversity in today's catch and deep time.
There appears to be a link between double-serrated teeth and huge body size: Tiger sharks, with a maximum length of 5.5 meters, are among the largest predatory sharks in our waters.
Furthermore, we find in their extinct cousins that the giant species had double-serrated teeth, but the smaller species only had single serrations, added second author Patrick L. Jambura of the University of Vienna's Department of Palaeontology.
