Only one partial skeleton that includes both forelimb and hindlimb elements has been reported for Australopithecus afarensis. The diminutive size of this specimen (A.L. 288-1 ["Lucy"]) has hampered our understanding of the paleobiology of this species absent the potential impact of allometry. Here we describe a large-bodied (i.e., well within the range of living Homo) specimen that, at 3.58 Ma, also substantially antedates A.L. 288-1. It provides fundamental evidence of limb proportions, thoracic form, and locomotor heritage in Australopithecus afarensis. Together, these characteristics further establish that bipedality in Australopithecus was highly evolved and that thoracic form differed substantially from that of either extant African ape.bipedality | human evolution | upright walking | hominid | thorax

Middle Pliocene hominin species diversity has been a subject of debate over the past two decades, particularly after the naming of Australopithecus bahrelghazali and Kenyanthropus platyops in addition to the well-known species Australopithecus afarensis. Further analyses continue to support the proposal that several hominin species co-existed during this time period. Here we recognize a new hominin species (Australopithecus deyiremeda sp. nov.) from 3.3-3.5-million-year-old deposits in the Woranso-Mille study area, central Afar, Ethiopia. The new species from Woranso-Mille shows that there were at least two contemporaneous hominin species living in the Afar region of Ethiopia between 3.3 and 3.5 million years ago, and further confirms early hominin taxonomic diversity in eastern Africa during the Middle Pliocene epoch. The morphology of Au. deyiremeda also reinforces concerns related to dentognathic (that is, jaws and teeth) homoplasy in Plio-Pleistocene hominins, and shows that some dentognathic features traditionally associated with Paranthropus and Homo appeared in the fossil record earlier than previously thought.

Ammonites are moderately common in most of the Graneros Shale and Greenhorn Limestone, and 30 genera and 54 species were recognized. Almost all specimens occur as internal molds, and many are somewhat distorted. Ammonites from the Thatcher Limestone Member of the Graneros Shale are assigned to four genera. Conlinoceras is described as a new subgenus of Calycoceras, and Calycoceras (Conlinoceras) gilberti n. sp. is named as the type. Ammonites in the upper fossiliferous unit of the Graneros Shale are arranged in four zones, and there is some overlap in the vertical range of the species. In ascending order these zones are Calycoceras (Conlinoceras) gilberti, Acanthoceras granerosense n. sp., A. muldoonense n. sp., and A. amphibolmn Morrow. The unit also contains species of Stomohamites, Anisoceras, Idiohamites, Desmoceras (Pseudouhligella), Euomphaloceras, Tarrantoceras, Epengonoceras, Borissiakoceras, and the new subspecies Turrilites (Turrilites) acutus Passy subsp. americanus. Only four genera of ammonites (Turrilites, Acanthoceras, Calycocerasl and Metoicoceras) were found in the Lincoln Limestone Member of the Greenhorn Limestone. The Zone of Acanthoceras amphibolum ranges upward into the basal part of the member, and the Zone of Calycoceras! canitaurinum characterizes the upper part. STRATIGRAPHY AND AMMONITE FAUNA NEAR PUEBLO, COLORADO The thin calcarenite beds in the Hartland Shale Member contain bits of ammonites which represent at least four genera (Stomohamites, Calycocerasl, Tarrantocerasl, and Metoicoceras). Metoicoceras seems to be the commonest genus. Fresh exposures of the shale reveal small impressions of juvenile ammonites that may represent an undescribed genus related to Tarrantoceras. Ammonites of the Bridge Creek Limestone Member can be assigned to four zones from oldest to youngest Sciponoceras gracile, Watinoceras coloradoense, Mammites nodosoides, and Collignoniceras woollgari; some overlapping occurs in the upper two zones. At least 23 genera are present. Puebloites is described as a new genus whose type is P. corrugatus (Stanton); Greenhornoceras is described as a new subgenus of Vascoceras, and Vascoceras (Greenhornoceras) birchbyi n. sp. is the type. Other new species described from the Bridge Creek Limestone Member are Hemiptychoceras reesidei, Ampakabites collignoni, and Kanabiceras puebloense. In terms of the standard stages of the Cretaceous, a late Cenomanian age is assigned to the upper part of the Graneros Shale and to the Lincoln Limestone Member and Hartland Shale Member of the Greenhorn Limestone. The basal part (Sciponoceras gracile Zone) of the Bridge Creek Limestone Member, formerly assigned to the lower Turonian, is herein considered of latest Cenomanian age. The rest of the member is of early Turonian age. 150 I 1.1. OKLAHOMA 200 MILES _| ._i FIGURE 1. Map of Colorado and parts of adjoining States showing places of outcrop of the Greenhorn Limestone and Graneros Shale discussed in report.

No abstract

No abstract