restoration
anchiceratops rare compared other ceratopsians in area, , found near marine sediments, in both horseshoe canyon , dinosaur park formations. indicates anchiceratops may have lived in estuaries other ceratopsids did not live. flowering plants increasingly common still rare compared conifers, cycads , ferns made majority of ceratopsian diets.
in 1914 brown suggested distinctive frill , horn form of anchiceratops caused sexual selection , intra-species recognition, not explain differences between taxa difference in defence function. in 1959, wann langston jr. suggested anchiceratops engaged in semi-aquatic lifestyle. long snout have allowed animal cross deeper swamps walking, catching breath on water s surface , heavy frill have acted counterbalance point beak upwards. later paleontologists tended reject notion, emphasizing dinosaurs in general land animals, in 2012 mallon again suggested semi-aquatic lifestyle, modern hippopotamus, @ least specimen nmc 8547. explanation robustness , extreme musculature of limbs. mallon admitted small tail not swimming-organ.
in 1990 thomas lehman proposed anchiceratops sexually dimorphic genus, skull of a. longirostris represents female. other anchiceratops skulls larger, more robust, , have longer horns point more vertically proposed represent males. preliminary statistical analysis of anchiceratops specimens mallon (2012) revealed these variations in skull form not fall 2 distinct morphs, , more represent individual variation, forcing him reject hypothesis there 2 species. likewise there no proof of sexual dimorphism.
in 2012, jordan cole mallon e.a. pointed out anchicertops ornatus species exceptionally long-lived; other ceratopsid species typically last few hundred thousand years. several possible explanations given: decreased competition related species; less habitat fragmentation recession of western interior seaway; , more generalist lifestyle.
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