Fig 1.
Locality map of occurrences of Albertocetus meffordorum in North and South Carolina.
(A) and a geologic map of Charleston, South Carolina (B), skeletal reconstruction of Albertocetus meffordorum with preserved elements in red (C), generalized stratigraphy at Belgrade Quarry (D) after [29], and generalized Paleogene stratigraphy of the Charleston area (E) after [24, 71]. Gray in geologic map denotes Ashley Formation and black denotes Chandler Bridge Formation. Geologic map simplified and redrawn after Weems and Lewis [26]. 87Sr/86Sr dates after [24, 31, 32].
Fig 2.
Cranium of Albertocetus meffordorum.
CCNHM 303 in (A) dorsal view; CCNHM 218 in (B) dorsal view; maxilla fragment of CCNHM 303 in (C) lateral, (D) ventral, and (E) medial view. Cross-hatching denotes damaged or missing bone.
Table 1.
Cranial measurements of Albertocetus meffordorum.
Fig 3.
Cranium of Albertocetus meffordorum in ventral view; CCNHM 303 (A) and CCNHM 218 (B).
Fig 4.
Cranium and mandible of Albertocetus meffordorum.
CCNHM 303 in (A) left lateral view and (B) posterior view; CCNHM 218 in (C) left lateral and (D) posterior view. Mandible in (E) lateral and (F) medial view.
Fig 5.
Basicranium of Albertocetus meffordorum (CCNHM 303) in ventral view, after (A) and prior to (B) removal of the petrosal and attachment of the paroccipital process.
Fig 6.
Albertocetus meffordorum endocast (CCNHM 218) in (A) dorsal, (B) ventral, (C) anterior, (D) right lateral, (E) left lateral, (F) anterodorsolateral, and (G) posterolateral views; (H), photograph of skull showing positions of CT slices; (I-L) CT slices of interorbital region showing ethmoid labyrinth.
Abbreviations: IM, Inferior Meatus; MM, Middle Meatus; SM, Superior Meatus.
Fig 7.
Petrosal of Albertocetus meffordorum (CCNHM 303) in ventral (A), dorsal (B), medial (C), and lateral (D) view.
Table 2.
Petrosal measurements of Albertocetus meffordorum.
Fig 8.
Petrosals of Albertocetus meffordorum and Echovenator sp. from the Ashley Formation and Belgrade Formation of South and North Carolina (respectively).
Albertocetus meffordorum, CCNHM 303 (Ashley Fm., SC) in ventral (A) and dorsal (B) view, and USNM 559392 (Belgrade Fm., NC) in ventral (C) and dorsal (D) view; Echovenator sp., USNM 534010 (Belgrade Fm., NC) in ventral (E) and dorsal (F) view, and CCNHM 1188 (Belgrade Fm., NC) in ventral (G) and dorsal (H) view.
Fig 9.
Tympanic bullae of Albertocetus meffordorum (CCNHM 303).
Left bulla in (A) medial, (B) dorsal, (C) lateral, and (D) medial view; right bulla in (E) medial and (F) lateral view.
Table 3.
Tympanic bulla measurements of Albertocetus meffordorum.
Fig 10.
Atlas and axis of Albertocetus meffordorum (CCNHM 303).
Atlas in (A) anterior, (B) posterior, (C) dorsal, and (D) left lateral view; Axis in (E) anterior, (F) posterior, (G) dorsal, and (H) left lateral view.
Fig 11.
Vertebrae and chevron (Ch) of Albertocetus meffordorum (CCNHM 303) in anterior view.
Absolute and relative vertebral positions from text.
Fig 12.
Vertebrae and chevron (Ch) of Albertocetus meffordorum (CCNHM 303) in posterior view.
Absolute and relative vertebral positions from text.
Fig 13.
Vertebrae and chevron (Ch) of Albertocetus meffordorum (CCNHM 303) in left lateral view.
Absolute and relative vertebral positions from text. C6, LE, and LF, are photographed in right lateral view and shown reversed for consistency.
Table 4.
Atlas and axis vertebra measurements of Albertocetus meffordorum (CCNHM 303).
Table 5.
Vertebral measurements of Albertocetus meffordorum (CCNHM 303).
Fig 14.
Ribs of Albertocetus meffordorum (CCNHM 303) in posterior view (left) and anterior view (right); positions uncertain.
Fig 15.
Feeding traces on postcranial elements of Albertocetus meffordorum (CCNHM 303).
Traces on the transverse process of LE (A), transverse process of LD (B), and chevron (C).
Fig 16.
Mean log encephalization quotients (EQ0.67) of cetaceans through time.
Archaeocetes are shown as blue squares, stem odontocetes as yellow circles, non-delphinoid crown odontocetes as red circles, and delphinoids as green circles; one mysticete is shown as a white square. Data presented in S1 Table.
Fig 17.
Vertebral proportions (centrum height/centrum breadth) by position of Albertocetus meffordorum, Balaenoptera acutorostrata, Delphinapterus leucas, Dorudon atrox, Feresa attenuata, and Physeter macrocephalus.
Data from Omura [72], Omura et al. [73], Yamada [74], Uhen [16], and this study (Table 5).