75 a high hwi is linked to long distance flight

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A high HWI is linked to long- distance flight ability HWI (“hand- wing index”) is a measure of wing shape - the ratio of a bird’s wing length to its width Round eggs require a wider pelvis than ones that are more elongated. Thus, just as birds that spend most of their time airborne have evolved more streamlined bodies and lighter, small skeletons, they have also evolved streamlined egg shapes to fit through the pelvis 76
Evolutionary patterns of eggshape diversity. A phylogeny of 1209 species in the sample for which molecular sequence data exist. For each species, the average egg length (light blue), asymmetry (medium blue), and ellipticity (dark blue) are represented by line lengths at branch tips. 77
The relationship between flying ability and egg shape does have exceptions, though. For example, whereas ostrich eggs tend to be spherical, kiwi eggs are elliptical—even though both species don’t fly. ??? Penguins also lay asymmetrical eggs, not for flight but because of their streamlined body plans, designed for powerful underwater swimming. 78
Intraspecific variation in social systems …… Spotted Hyenas (H. Kruuk) Serengeti populations usually solitary and nomadic. Scavengers. Ngorongoro Crater populations live in large cohesive social groups that defend territories and hunt. Larger more abundant prey. When prey is high on the Serengeti, hyenas will form social groups and hunt. facultative behavior 79
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Intraspecific variation in social systems …… Spotted Hyenas (H. Kruuk) Serengeti populations usually solitary and nomadic. Scavengers. Ngorongoro Crater populations live in large cohesive social groups that defend territories and hunt. Larger more abundant prey. When prey is high on the Serengeti, hyenas will form social groups and hunt. facultative behavior 81