Mosaic habitats at Woranso-Mille (Ethiopia) during the Pliocene and implications for Australopithecus paleoecology and taxonomic diversity

Su, Denise F.; Haile‐Selassie, Yohannes

doi:10.1016/j.jhevol.2021.103076

Cited by 12 publications

(3 citation statements)

References 94 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The expansion of more open and arid habitats is thought to have been a catalyst for many changes in hominin behavior, anatomy, and/or physiology over the past 10 Ma (3,(55)(56)(57)(58). This includes the emergence of hominin bipedalism in the late Miocene-Pliocene as fossils of the earliest ( putative) hominins, and multiple australopith taxa are found within savanna-mosaic, rather than closed forest, paleohabitats (9)(10)(11)(12)(13). What remains unclear, however, is what type of selective pressure acted on hominins because of this transition into open habitats since contrasting signals of terrestriality and arboreality leave much uncertainty as to how exactly hominins used these habitats (15,18).…”

Section: The Hominin Arboreal Nichementioning

confidence: 99%

“…Paleoenvironmental reconstructions indicate that early hominins were not living in tropical forests common to most extant apes today ( 2 , 3 ). Instead, the earliest (putative) fossil hominins, including Orrorin (6 Ma) ( 9 ), Ardipithecus (5.8 to 4.4 Ma) ( 10 , 11 ), and early Australopithecus (4.2 to 2.9 Ma) ( 12 , 13 ), would have moved and foraged in mosaic savanna habitats dominated by woodland with strips of riparian forest vegetation, often termed “savanna-woodland” or “savanna-mosaic” (used hereafter). Compared to tropical forest, these savanna-mosaic habitats would have elicited different selective pressures associated with reduced tree density and increased seasonality ( 14 , 15 ).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Wild chimpanzee behavior suggests that a savanna-mosaic habitat did not support the emergence of hominin terrestrial bipedalism

et al. 2022

View full text Add to dashboard Cite

Bipedalism, a defining feature of the human lineage, is thought to have evolved as forests retreated in the late Miocene-Pliocene. Chimpanzees living in analogous habitats to early hominins offer a unique opportunity to investigate the ecological drivers of bipedalism that cannot be addressed via the fossil record alone. We investigated positional behavior and terrestriality in a savanna-mosaic community of chimpanzees ( Pan troglodytes schweinfurthii ) in the Issa Valley, Tanzania as the first test in a living ape of the hypothesis that wooded, savanna habitats were a catalyst for terrestrial bipedalism. Contrary to widely accepted hypotheses of increased terrestriality selecting for habitual bipedalism, results indicate that trees remained an essential component of the hominin adaptive niche, with bipedalism evolving in an arboreal context, likely driven by foraging strategy.

show abstract

Section: The Hominin Arboreal Nichementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Wild chimpanzee behavior suggests that a savanna-mosaic habitat did not support the emergence of hominin terrestrial bipedalism

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Understanding how ape locomotor or manipulative behaviors vary within and among different landscapes offers a unique opportunity to investigate the potential ecological drivers of bipedalism, arboreality, or changes in foraging strategy in a large‐bodied, semi‐arboreal ape that cannot be investigated from fossil evidence alone. This is particularly true of chimpanzees living in savanna‐mosaic landscapes that are analogous to those reconstructed for early hominins (e.g., Senut et al, 2001; Su & Haile‐Selassie, 2022; White et al, 2009), such as Issa Valley, Tanzania (Drummond‐Clarke et al, 2022; Giuliano et al, 2022; Piel et al, 2017) or Fongoli, Senegal (Pruetz et al, 2015; Wessling et al, 2018). The chimpanzees in the Issa Valley occasionally climb steep, rocky outcrops (Drummond‐Clarke et al, 2022), offering a valuable opportunity to investigate the potential influence that petrous climbing may have played in hominin locomotion and hand morphology (also see Everett et al (2021)).…”

Section: Part 3: Evolutionmentioning

confidence: 99%

Form, function and evolution of the human hand

Kivell

Baraki

Lockwood

et al. 2022

American Journal of Biological Anthropology

View full text Add to dashboard Cite

The modern human hand is an intriguing mix of primitive morphology and derived function. Traditionally, its form and function are explained as a functional “trade‐off” between the requirements of locomotion and manipulation, but recently acquired comparative, experimental and fossil evidence suggests that this functional trade‐off is more complex than conventional wisdom suggests. Moreover, when studying hand evolution within the hominin clade, the only morphological evidence comes from the hard‐tissues, and evidence about hand function must be inferred indirectly from the archaeological record. We lack information about critical aspects of hand form (e.g., soft tissues) and function (e.g., neurology) as well as non‐lithic evidence about behavior. Thus, comparative anatomical, experimental and ethological studies of modern humans and other primates are critical to making more informed inferences about hand use in the past. We review the relevant fossil and archaeological evidence within the relevant comparative context (e.g., other extant apes and dexterous monkeys) in an attempt to reconstruct hand evolution within the hominin clade. We conclude by summarizing our current understanding—or lack thereof—of the evolutionary history of the modern human hand.

show abstract

Sex differences in positional behavior of chimpanzees (Pan troglodytes schweinfurthii) living in the dry and open habitat of Issa Valley, Tanzania

Drummond‐Clarke,

Kivell,

Sarringhaus

et al. 2024

American Journal of Biological Anthropology

View full text Add to dashboard Cite

ObjectivesMany early fossil hominins are associated with savanna‐mosaic paleohabitats, and high sexual dimorphism that may reflect differences in positional behavior between sexes. However, reconstructions of hominin behavior and the selective pressures they faced in an open habitat are limited by a lack of studies of extant apes living in contemporary, analogous habitats. Here, we describe adult chimpanzee positional behavior in the savanna‐mosaic habitat of the Issa Valley, Tanzania, to test whether Issa chimpanzees show larger sex‐differences in positional behavior than their forest‐dwelling counterparts.Materials and MethodsWe quantified and compared adult locomotor and postural behavior across sexes (6 females, 7 males) in the riparian forest (closed) and miombo woodland (open) vegetation types at Issa Valley (13,743 focal observations). We then compared our results to published data of chimpanzee communities living in more forested habitats.ResultsIssa females and males both spent less time arboreally in open vegetation and showed similar locomotor and postural behavior on the same substrates, notably using a high level of suspensory locomotion when arboreal. Females were, however, more arboreal than males during locomotor behavior, as well as compared with females from other communities. Issa males behaved similarly to males from other communities.ConclusionResults suggest that open habitats do not elicit less arboreal behaviors in either sex, and may even select for suspensory locomotion to effectively navigate an open canopy. An open habitat may, however, increase sex differences in positional behavior by driving female arboreality. We suggest this is because of higher energetic demands and predator pressures associated with open vegetation, which are likely exaggerated for reproducing females. These results have implications for the interpretation of how sexual dimorphism may influence reconstructions of hominin positional behavior.

show abstract

Mosaic habitats at Woranso-Mille (Ethiopia) during the Pliocene and implications for Australopithecus paleoecology and taxonomic diversity

Cited by 12 publications

References 94 publications

Wild chimpanzee behavior suggests that a savanna-mosaic habitat did not support the emergence of hominin terrestrial bipedalism

Wild chimpanzee behavior suggests that a savanna-mosaic habitat did not support the emergence of hominin terrestrial bipedalism

Form, function and evolution of the human hand

Sex differences in positional behavior of chimpanzees (Pan troglodytes schweinfurthii) living in the dry and open habitat of Issa Valley, Tanzania

Contact Info

Product

Resources

About