عنوان

Hominin Dietary Niche Breadth Expansion During Pliocene Environmental Change in Eastern Africa

شماره

TL52652

زبان متن نوشتاري يا گفتاري و مانند آن

انگلیسی

عنوان اصلي

Hominin Dietary Niche Breadth Expansion During Pliocene Environmental Change in Eastern Africa

نام عام مواد

[Thesis]

نام نخستين پديدآور

Seyoum, Chalachew Mesfin

نام ساير پديدآوران

Kimbel, William H.

نام ناشر، پخش کننده و غيره

Arizona State University

تاریخ نشرو بخش و غیره

2020

متن يادداشت

139 p.

جزئيات پايان نامه و نوع درجه آن

Ph.D.

کسي که مدرک را اعطا کرده

Arizona State University

امتياز متن

2020

متن يادداشت

Stable carbon isotope data for early Pliocene hominins Ardipithecus ramidus and Australopithecus anamensis show narrow, C3-dominated isotopic signatures. Conversely, mid-Pliocene Au. afarensis has a wider isotopic distribution and consumed both C3 and C4 plants, indicating a transition to a broader dietary niche by ~ 3.5 million years ago (Ma). Dietary breadth is an important aspect of the modern human adaptive suite, but why hominins expanded their dietary niche ~ 3.5 Ma is poorly understood at present. Eastern Africa has produced a rich Pliocene record of hominin species and associated mammalian faunas that can be used to address this question. This dissertation hypothesizes that the shift in hominin dietary breadth was driven by a transition to more open and seasonal environments in which food resources were more patchily distributed both spatially and temporally. To this end, I use a multiproxy approach that combines hypsodonty, mesowear, faunal abundance, and stable isotope data for temporally well-constrained early and mid-Pliocene mammal assemblages (5.3-2.95 Ma) from Ethiopia, Kenya, and Tanzania to infer patterns of environmental change through time. Hypsodonty analyses revealed that early Pliocene sites had higher annual precipitation, lower precipitation seasonality, and lower temperature seasonality than mid-Pliocene sites. Mesowear analyses, however, did not show from attrition- to abrasion- dominated wear through time. Abundance data suggest that there was a trend towards aridity, as Tragelaphini (woodland antelope) decline while Alcelaphini (grassland antelope) increased in abundance through time. Carbon isotope data indicate that most taxa shifted to diets focusing on C4 grasses through time, which closely follows paleosol carbon isotope data documenting the expansion of grassland ecosystems in eastern Africa. Overall, the results suggest Ar. ramidus and Au. anamensis preferentially exploited habitats in which preferred food resources were likely available year-round, whereas Au. afarensis lived in more variable, seasonal environments in which preferred foods were available seasonally. Au. afarensis and K. platyops likely expanded their dietary niche in less stable environments, as reflected in their wider isotopic niche breadth.

اصطلاح موضوعی

African studies

اصطلاح موضوعی

Paleoecology

مستند نام اشخاص تاييد نشده

Seyoum, Chalachew Mesfin

مستند نام اشخاص تاييد نشده

Kimbel, William H.

مستند نام تنالگان تاييد نشده

Arizona State University

نام الکترونيکي

فرمت انتشار

p

نوع ماده

[Thesis]

کد کاربرگه

276903

سطح دسترسي

a

تكميل شده

Y