Both the American horned lizards (Phyrnosoma, Phrynosomatidae) and the Australian thorny devil (Moloch horridus, Agamidae) eat ants almost exclusively
Suggest an explanation for the convergence of ant-eating specialists in these two families on a short-legged, stocky body form and a spine-covered body.
Ants have a large amount of keratinized exoskeleton in relation to their internal contents. The lizards cannot digest the exoskeleton, so they must eat large numbers of ants to obtain the energy they need; the stocky body form is probably needed to accommodate a large stomach and intestine. These lizards capture ants on the substrate and do not have to chase them, so long legs would probably be more hindrance than help. A stocky, short-legged lizard cannot run to escape predators, and the spines provide a measure of defense. (E. R. Pianka and H. D. Pianka. 1970 . The Ecology of Moloch horridus (Lacertilia: Agamidae) in Western Australia. Copeia 1970:90-103; and E. R. Pianka and W. S. Parker. 1975 . Ecology of horned lizards: A review with special reference to Phrynosoma platyrhinos. Copeia 1975:141-162)
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Answer the following statement true (T) or false (F)