Sharp and fully loaded: 3D tissue reconstruction reveals how snake fangs stay deadly during fang replacement

et al. 2023

Preprint

1. The structure, composition, and shape of teeth have been related to dietary specialization in many vertebrate species, except snakes. Yet, snakes have diverse dietary habits that may impact the shape of their teeth. We hypothesize that prey properties, such as hardness and shape, as well as feeding behavior, such as aquatic or arboreal predation, or holding vigorous prey, impose constraints on the evolution of tooth shape in snakes. 2. We compared the morphology of the dentary teeth of 63 species that cover the phylogenetic and dietary diversity of snakes, using 3D geometric morphometrics and linear measurements. 3. Our results show that prey hardness, foraging substrate and the main mechanical challenge are important drivers of tooth shape, size, and curvature. 4. Overall, long, slender, curved teeth with a thin layer of hard tissue are observed in species that need to maintain a grip on their prey. Short, stout, less curved teeth are associated with species that undergo high or repeated loads. 5. Our study demonstrates the diversity of tooth morphology in snakes and the need to investigate its underlying functional implications to better understand the evolution of teeth in vertebrates.

Section: Introductionmentioning

confidence: 99%

Armed to the teeth: the underestimated diversity in tooth shape in snakes and its relation to feeding behavior and diet.

et al. 2023

Preprint

“…Despite their richness and complexity in shape (Vaeth et al, 1985 ; Young & Kardong, 1996 ), studies on snake tooth morphology are scarce and either lack a quantitative approach or are phylogenetically limited (Berkovitz & Shellis, 2017 ; Britt et al, 2009 ; Evans et al, 2019 ; Rajabizadeh et al, 2020 ; Ryerson & Van Valkenburgh, 2021 ). Fangs, and mostly front fangs, have recently attracted some scientific attention (Broeckhoven & du Plessis, 2017 ; Cleuren, Parker, et al, 2021 ; Crofts et al, 2019 ; Kundanati et al, 2020 ; Palci et al, 2021 ; Plessis et al, 2018 ). Yet, fangs are phylogenetically and functionally limited; their only purpose is to puncture the prey to deliver venom and consequently, fangs are not representative of snake tooth diversity.…”

Section: Introductionmentioning

confidence: 99%

Armed to the teeth: The underestimated diversity in tooth shape in snakes and its relation to feeding behavior and diet

et al. 2023

Ecology and Evolution

The structure, composition, and shape of teeth have been related to dietary specialization in many vertebrate species, but comparative studies on snakes' teeth are lacking. Yet, snakes have diverse dietary habits that may impact the shape of their teeth. We hypothesize that prey properties, such as hardness and shape, as well as feeding behavior, such as aquatic or arboreal predation, or holding vigorous prey, impose constraints on the evolution of tooth shape in snakes. We compared the morphology of the dentary teeth of 63 species that cover the phylogenetic and dietary diversity of snakes, using 3D geometric morphometrics and linear measurements. Our results show that prey hardness, foraging substrate, and the main feeding mechanical challenge are important drivers of tooth shape, size, and curvature. Overall, long, slender, curved teeth with a thin layer of hard tissue are observed in species that need to maintain a grip on their prey. Short, stout, less curved teeth are associated with species that undergo high or repeated loads. Our study demonstrates the diversity of tooth morphology in snakes and the need to investigate its underlying functional implications to better understand the evolution of teeth in vertebrates.

“…Despite their richness and complexity in shape [15,16], studies on snake tooth morphology are scarce and either lack of a quantitative approach or are phylogenetically limited [11,[17][18][19][20]. Fangs, and mostly front fangs, have recently attracted some scientific attention [21][22][23][24][25][26]. Yet, fangs are phylogenetically and functionally limited as their only purpose is to puncture the prey to deliver venom under the skin, and they are two highly derived teeth of over a hundred (for some species) that are involved in the whole feeding sequence.…”

Section: Introductionmentioning

confidence: 99%

Armed to the teeth: the underestimated diversity in tooth shape in snakes and its relationship to feeding constraints

et al. 2022

Preprint

Teeth are one of the most studied hard tissues in vertebrates. Their structure, composition and shape are related to dietary specialization in many species. At first glance, snake teeth all look similar; conical, sharp, curved. Yet, snakes, like other vertebrates, have very diverse diets that may have affected their shape. We compared the morphology of the teeth of 63 species that cover both the phylogenetic and dietary diversity of snakes. We predicted that prey properties play a role in shaping snakes teeth along with their feeding behavior. Limblessness combined to the peculiar feeding behavior of snakes impose strong functional constraints on their teeth, especially during arboreal or aquatic feeding. Our results show that prey hardness, foraging substrate and the main feeding constraint are drivers of tooth shape, size, and curvature. We highlight two main morphotypes: long, slender, curved with a thin layer of hard tissue for snakes that need a good grip on their prey and short, stout, less curved teeth in snakes that eat hard or long prey. Our study demonstrates the diversity of tooth morphology in snakes and the need to investigate the underlying functional implications to better understand the evolution of teeth in vertebrates.