Durophagy

Jaws and teeth of Rhinoptera bonasus (cownose ray)

Durophagy is the eating behavior of animals that consume hard-shelled or exoskeleton-bearing organisms, such as corals, shelled mollusks, or crabs.[1] It is mostly used to describe fish, but is also used when describing reptiles,[2] including fossil turtles,[3] placodonts and invertebrates, as well as "bone-crushing" mammalian carnivores such as hyenas.[4] Durophagy requires special adaptions, such as blunt, strong teeth and a heavy jaw.[5] Bite force is necessary to overcome the physical constraints of consuming more durable prey and gain a competitive advantage over other organisms by gaining access to more diverse or exclusive food resources earlier in life.[6] Those with greater bite forces require less time to consume certain prey items as a greater bite force can increase the net rate of energy intake when foraging and enhance fitness in durophagous species.

In the order Carnivora there are two dietary categories of durophagy; bonecrackers and bamboo eaters. Bonecrackers are exemplified by hyenas and borophagines, while bamboo eaters are primarily the giant panda and the red panda. Both have developed similar cranial morphology. However, the mandible morphology reveals more about their dietary resources. Both have a raised and dome-like anterior cranium, enlarged areas for the attachment of masticatory muscles, enlarged premolars, and reinforced tooth enamel. Bamboo eaters tend to have larger mandibles, while bonecrackers have more sophisticated premolars.[7]

  1. ^ Huber, Daniel R.; Dean, Mason N.; Summers, Adam P. (2008-08-06). "Hard prey, soft jaws and the ontogeny of feeding mechanics in the spotted ratfish Hydrolagus colliei". Journal of the Royal Society Interface. 5 (25): 941–953. doi:10.1098/rsif.2007.1325. ISSN 1742-5689. PMC 2607471. PMID 18238758.
  2. ^ Pregill, Gregory (1984). "Durophagous Feeding Adaptations in an Amphisbaenid". Journal of Herpetology. 18 (2): 186–191. doi:10.2307/1563747. JSTOR 1563747.
  3. ^ Myers, Timothy S.; Polcyn, Michael J.; Mateus, Octávio; Vineyard, Diana P.; Gonçalves, António O.; Jacobs, Louis L. (2017-11-13). "Phylogeny". Data from: A new durophagous stem cheloniid turtle from the lower Paleocene of Cabinda, Angola (Data Set). Dryad Digital Repository. doi:10.5061/dryad.n618q.
  4. ^ Tseng, Zhijie Jack; Wang, Xiaoming (2010-11-01). "Cranial functional morphology of fossil dogs and adaptation for durophagy in Borophagus and Epicyon (Carnivora, Mammalia)". Journal of Morphology. 271 (11): 1386–1398. doi:10.1002/jmor.10881. ISSN 1097-4687. PMID 20799339. S2CID 7150911.
  5. ^ Huber, Daniel R.; Eason, Thomas G.; Hueter, Robert E.; Motta, Philip J. (2005-09-15). "Analysis of the bite force and mechanical design of the feeding mechanism of the durophagous horn shark Heterodontus francisci". Journal of Experimental Biology. 208 (18): 3553–3571. doi:10.1242/jeb.01816. ISSN 0022-0949. PMID 16155227.
  6. ^ Pfaller, Joseph B.; Gignac, Paul M.; Erickson, Gregory M. (2011-05-15). "Ontogenetic changes in jaw-muscle architecture facilitate durophagy in the turtle Sternotherus minor". Journal of Experimental Biology. 214 (10): 1655–1667. doi:10.1242/jeb.048090. ISSN 0022-0949. PMID 21525311.
  7. ^ Figueirido, Borja; Tseng, Zhijie Jack; Martín-Serra, Alberto (2013-07-01). "Skull Shape Evolution in Durophagous Carnivorans". Evolution. 67 (7): 1975–1993. doi:10.1111/evo.12059. ISSN 1558-5646. PMID 23815654. S2CID 23918004.