You present graphics in order to deceive rather than educate which is why you have no problem with falsely claiming Pakicetus had webbed feet and was aquatic.
In fact, another here on this same thread engages in the same dishonest trickery, namely the use of graphics to try to reinforce false logic. The claim is because some animals can be excellent climbers or swimmers that somehow the depiction of webbed feet makes sense, but in reality, it is the exact opposite. There is no need to fabricate webbed feet because there is no reason for a land animal to need webbed feet to swim.
But the fact remains that these critters had webbed feet.
I call it deception because it's presenting false data and statements, and whether it's Haeckel's forged drawings, Pakicetus being presented with webbed feet
And what about Rodhocetus, eh? It has "an astragalus and cuboid in the ankle with characteristics diagnostic of artiodactyls", yet was a swimmer with webbed feet. How do we know? We look at the bones.
Here's the blighter, and I defy you to claim it's not related to the Pakicetus and Ambulocetus pics above.
Gingerich et al (2001) 'Origin of Whales from Early Artiodactyls: Hands and Feet of Eocene Protocetidae from Pakistan', Science Vol 293 no 5538, pp. 2239 - 2242.
quote:
Articulations both with the tarsus and with the phalanges indicate that the metatarsals were sometimes well separated. Contraction of intrinsic muscles narrowed the foot when it was tightly flexed. Unusual flanges of bone on the proximomedial base of middle phalanges II and III and on the proximolateral base of middle phalanges IV and V (arrows in Fig. 2C) provided leverage for opening the feet to maximum breadth during extension. Pedal phalanges cannot have been weight-bearing, but were elongated to stiffen a large webbed foot. On land Rodhocetus evidently walked on the plantar surface of the foot, with the calcaneum, plantar processes of other tarsals, and metatarsal sesamoids bearing weight, somewhat like eared seals do today. The structure of the hand is consistent with limited locomotion on land, but the foot shows that Rodhocetus was predominantly aquatic rather than terrestrial.
A skeletal restoration of Rodhocetus is shown in Fig. 3. Metapodials and phalanges of the hands and feet are similar to those described for Ambulocetus natans (7, 36), but the hands of Rodhocetus are longer (about 165% of radius length in Rodhocetus, compared with 145% of radius length in Ambulocetus) and the feet are even longer (about 279% of radius length and 158% of femur length in Rodhocetus, compared with 197% of radius length and 121% of femur length in Ambulocetus). Thewissen and Fish (37) interpreted Ambulocetus as an otter-like pelvic paddler, and this is a good model for Rodhocetus. If the hands and feet were webbed as inferred here, then Rodhocetus was probably capable of quadrupedal paddling as well as pelvic paddling.
quote:
Fig. 2. Right astragalus and cuboid (A) of Artiocetus clavis, new genus and species, GSP-UM 3458, compared with virtually complete left manus (B) and left pes (C) of Rodhocetus balochistanensis, new species, GSP-UM 3485 (pes reversed from right side). All are shown in anterior view. Elements with oblique hatching were not recovered. Note artiodactyl characteristics in the well-developed navicular trochlea on the head of the astragalus, convex fibular facet on the calcaneum, and concave astragalar facet paired with a convex calcaneal facet notched into the cuboid. The hand is mesaxonic with three central weight-bearing toes that evidently bore nail-like hooves (distal phalanges preserved on digits II and IV) flanked by more gracile lateral toes that lacked hooves [distal phalanx preserved on digit I; see (29)]. The foot is paraxonic with four long toes, flanges of bone on the medial or lateral bases of the middle phalanges (arrows) providing leverage for opening the feet to maximum breadth during extension, and narrowly pointed ungules (distal phalanges preserved on digits II and III). Abbreviations: Ast., astragalus; ast. f., astragalar facet; Cal., calcaneum; cal. f., calcaneal facet; Cub., cuboid; Cun., cuneiform; fib. f., fibular facet; Lun., lunar; Mc, metacarpal; Mt, metatarsal; Nav., navicular; nav. tr., navicular trochlea; Pis., pisiform; Sca., scaphoid; tib. tr., tibial trochlea; Tra., trapezium; Unc., unciform. Trapezoid and magnum are present in carpus but not separately labeled.
Sure, it's an inference. You do realise that it is an
inference that fossils are the remains of past organisms at all, yeah?
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