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Verbal·Information and Ideas·Command of Evidence
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Average Frontation Angle for Five Species, by Family, Habitat, and Preferred Substrate
SpeciesFamilyHabitatPreferred substrateFrontation angle ()
Vulpes lagopusCanidaeopenterrestrial54.89
Nyctereutes procyonoidesCanidaeclosedarboreal56.51
Lynx lynxFelidaeclosedterrestrial65.67
Leptailurus servalFelidaeopenterrestrial65.80
Leopardus wiediiFelidaeclosedarboreal67.61
By examining trait distributions across phylogenetic lineages, evolutionary biologists can determine whether trait similarities result from shared ancestry, leading to consistent presence of the trait among closely related species, or from convergent evolution under similar selective pressures, leading to the independent appearance of the trait in more distantly related species occupying similar ecological niches. Hypothesizing that orbit (eye socket) orientation in the families Canidae and Felidae (both within the order Carnivora) is primarily driven by the latter mechanism, a researcher measured frontation angles—the extent to which orbits face downward or upward—in felid and canid species occupying various habitats and preferring different substrates.
Assuming the data in the table are broadly representative, do the data support the researcher’s hypothesis as presented in the text?
A
Yes, because frontation angles show a moderately strong relationship with ecological niches, with two out of the three species with the highest frontation angles either inhabiting closed habitats or preferring terrestrial substrates
B
Yes, because frontation angles are lower for canid species than for felid species regardless of habitat or preferred substrate, with values for species from the same taxonomic family clustering in a relatively narrow range
C
No, because frontation angles cluster by taxonomic family rather than by ecological categories, with similar values measured for species from the same family despite their occupation of different ecological niches
D
No, because frontation angles are relatively consistent across ecological categories, with values for species inhabiting closed arboreal habitats and species inhabiting open terrestrial habitats ranging from 56.51 to 67.61 and from 54.89 to 65.80, respectively