Pollen evidence of the palaeoenvironments of Lufengpithecus lufengensis in the Zhaotong Basin, southeastern margin of the Tibetan Plateau

Abstract

Evolutionary processes in hominoid primates were closely related to global and/or regional environmental changes, and therefore palaeoenvironmental reconstruction is fundamental for understanding how environmental changes shaped their evolution. Here, we present pollen data from the 16-m-thick Shuitangba (STB) section, Yunnan Province, southwestern China, bearing remains of the hominoid Lufengpithecus lufengensis of the terminal Miocene; and use principal component analysis to reconstruct the palaeovegetation and palaeoclimate during the key period when the hominoid lived. Our results show that before the STB hominoid appeared (Zone A), the vegetation was dominated by subtropical evergreen broad-leaved taxa with a few temperate deciduous taxa (e.g., Quercus, Castanea/Castanopsis, Alnus). The development of aquatic plants commencing at the~12 m depth is a prominent feature, indicating a warm and humid climate. During the time when the hominoid lived (Zone B), evergreen broad-leaved forests with evergreen Quercus were predominant, while grasses including Poaceae began to expand, and simultaneously conifers decreased, indicating a warm climate. The significant presence of aquatic pollen taxa in subzone A-2 and Zone B suggests the occurrence of lacustrine or swampy environments. In contrast, in Zone C, the vegetation changed to coniferous forest, indicating cooler and drier conditions. These results provide substantive evidence of the vegetation conditions when the hominoid lived, suggesting that the greater diversity of vegetation and the warm humid climate, compared to the present day, would have favoured its survival.

A new otter of giant size,Siamogale melilutrasp. nov. (Lutrinae: Mustelidae: Carnivora), from the latest Miocene Shuitangba site in north-eastern Yunnan, south-western China, and a total-evidence phylogeny of lutrines

“…This aquatic plant is consistent with a shallow lake or swamp environment in a mildly warm and humid climate, also confirmed by sedimentological studies (Zhang et al 2016). Pollen studies suggest a flora associated with the vertebrate fossils of evergreen broad-leaved forests with evergreen Quercus as the most dominant element, with expansion of grasses (including Poaceae) and decline of conifers at the otter (and hominoid)-producing horizon (Chang et al 2015).…”

Late Miocene Climate Cooling Contributed to the Disappearance of Hominoids in Yunnan Region, Southwestern China

“…lufengensis . Both pollen and clay minerology at the STB site indicate that the hominoids lived in a fairly warm and humid environment dominated by broad‐leaved evergreen forest, with evergreen Quercus being common (Chang et al, 2015; Zhang et al, 2016). Moreover, Huang et al (2017) hypothesize that the Shuitangba hominoid lived in a stratified mixed forest composed of trees, shrubs, lianas, herbs, and grasses, near a lake occupied by various aquatic plants (Huang et al, 2017).…”

“…The hominoid fossils from Yunnan are attributed to species of the genus Lufengpithecus , likely a stem member of the African ape and human clade (Kelley & Gao, 2012). During the last three decades, numerous studies have described the morphology of the fossils and reconstructed the hominoid paleohabitats during the late Miocene in the Yunnan region (e.g., Harrison et al, 2002; Jablonski et al, 2014; Chang et al, 2015; Ji et al, 2013; Zhang et al, 2016; others). The climate change is particularly important because the climate to a great extent determines the types of vegetation, which influence food and habitat availability across different spatial and temporal scales (Uno et al, 2016).…”

Fossil seeds of Euryale (Nymphaeaceae) indicate a lake or swamp environment in the late Miocene Zhaotong Basin of southwestern China

“…This interpretation is further strengthened by the presence of aquatic pollen in the hominoid-bearing layer [29]. As Euryale is an aquatic plant that lives in swamps and lakes with shallow and stable water, the fossil occurrence of Euryale may imply a swamp and/or lake environment with areas of shallow and stable water in the [28,30] and palynology [29], suggests that the Shuitangba hominoid may have lived in the vicinity of a lake and/or swamp.…”

“…1c). An outcrop section at the mine is *16 m thick, composed of seven sedimentary layers [29]. The upper part of the black peaty clay layer is bracketed by the middle and lower lignite layers ( Table 1).…”