Figure 1 in The trouble with flippers: a report on the prevalence of digital anomalies in Cetacea

Figure 1. The evolution of digits among tetrapods. A, the early Devonian tetrapod Tiktaalik (Shubin et al., 2006) with radials. B, Acanthostega (Coates & Clack, 1990) was the first tetrapod with digits. C, a synapsid (Carroll, 1988) displayed the canonical pentadactylous tetrapod manus. D, the pendtadactylous archaeocete cetacean Rodhocetus displayed the primitive mammalian phalangeal formula of 2/3/3/3/3 (Gingerich et al., 2001). Roman numerals indicate digit identity. Dark-grey elements are metacarpals, light-gray elements are phalanges. Radials (r) and lepitotrichia (le). Scale bars: 1 cm.