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text_A: Sanjay Gupta declined to fundraise and campaign for President Barack Obama.
text_B: Iguanodontidae is a family of iguanodontians belonging to Styracosterna , a derived clade within Ankylopollexia .. iguanodontians. iguanodontians. Styracosterna. Styracosterna. Ankylopollexia. Ankylopollexia. Some evidence dates the origination of Iguanodontidae to approximately 200 million years ago during the Jurassic Period in North America .. Jurassic. Jurassic. Jurassic Period. Jurassic Period. The most recent iguanodontid fossils have been dated to approximately 65 million years ago , which temporally corresponds with the Cretaceous-Paleogene extinction event .. Cretaceous-Paleogene extinction event. Cretaceous-Paleogene extinction event. Cretaceous. Cretaceous. Iguanodontids were most prevalent during the Early Cretaceous Period , and became widely distributed during this time .. Early Cretaceous. Early Cretaceous. Cretaceous. Cretaceous. Iguanodontids , characterized by their elongated maxillae , were herbivorous and typically large in size .. This family exhibited locomotive dynamism ; there exists evidence for both bipedalism and quadrupedalism within iguanodontid species , supporting the idea that individual organisms were capable of both locomoting exclusively with their hind limbs and locomoting quadrupedally .. bipedalism. bipedalism. quadrupedalism. quadrupedalism. Iguanodontids possess hoof-like second , third , and fourth digits , and in some cases , a specialized thumb spike and an opposable fifth digit .. Their skull construction allows for a strong chewing mechanism called a transverse power stroke .. This , paired with their bilateral dental occlusion , made them extremely effective as herbivores .. Members of Iguanodontidae are thought to have had a diet that consisted of both gymnosperms and angiosperms , the latter of which co-evolved with the iguanodontids in the Cretaceous period .. gymnosperms. gymnosperms. angiosperms. angiosperms. Cretaceous. Cretaceous. There is no consensus on the phylogeny of Iguanodontidae .. phylogeny. phylogeny. Iguanodontidae is most frequently characterized as paraphyletic with respect to Hadrosauridae , although some researchers advocate for a monophyletic view of the family .. paraphyletic. paraphyletic. Hadrosauridae. Hadrosauridae. monophyletic. monophyletic. Additionally , some analyses have supported a reduction of the number of constituent genera within Iguanodontidae .
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