Molecular phylogeny of mega-diverse Carabus attests late Miocene evolution of alpine environments in the Himalayan–Tibetan Orogen

Abstract

The timing, sequence, and scale of uplift of the Himalayan–Tibetan Orogen (HTO) are controversially debated. Many geoscientific studies assume paleoelevations close to present-day elevations and the existence of alpine environments across the HTO already in the late Paleogene, contradicting fossil data. Using molecular genetic data of ground beetles, we aim to reconstruct the paleoenvironmental history of the HTO, focusing on its southern margin (Himalayas, South Tibet). Based on a comprehensive sampling of extratropical Carabus, and ~ 10,000 bp of mitochondrial and nuclear DNA we applied Bayesian and Maximum likelihood methods to infer the phylogenetic relationships. We show that Carabus arrived in the HTO at the Oligocene–Miocene boundary. During the early Miocene, five lineages diversified in different parts of the HTO, initially in its southern center and on its eastern margin. Evolution of alpine taxa occurred during the late Miocene. There were apparently no habitats for Carabus before the late Oligocene. Until the Late Oligocene elevations must have been low throughout the HTO. Temperate forests emerged in South Tibet in the late Oligocene at the earliest. Alpine environments developed in the HTO from the late Miocene and, in large scale, during the Pliocene–Quaternary. Findings are consistent with fossil records but contrast with uplift models recovered from stable isotope paleoaltimetry.

Exploring Paleogene Tibet's warm temperate environments through target enrichment and phylogenetic niche modelling of Himalayan spiny frogs (Paini, Dicroglossidae)

“…The best‐fitting ARE model under the constraints of the paleoenvironmental scenario of Schmidt et al. (2023) was DIVALIKE, showing an extinction rate (‘e’) of 0.039 events/Myr, and an anagenetic dispersal rate (‘d’) of 0.055 events/Myr. The parameters and likelihoods of the three models assessed are summarized in Table S6.…”

“…Contrasting with the scenario of a highly elevated Paleogene Tibetan Plateau is the fossil record for the Cenozoic HTO (compiled in Schmidt et al., 2023; Spicer et al., 2021a), strongly supporting a lower general topography of significant parts of Tibet with tropical to temperate paleoenvironments until the Early Miocene (reviewed in Ai et al., 2019; Deng et al., 2019). However, insufficient age constraints on the fossil deposits introduce further uncertainties into the chronology of uplift models (Fang et al., 2020; Su et al., 2019).…”

“…However, insufficient age constraints on the fossil deposits introduce further uncertainties into the chronology of uplift models (Fang et al., 2020; Su et al., 2019). Despite these limitations, no fossils have been unearthed to substantiate the existence of cold temperate or alpine environments in the central and southern HTO during the Paleogene, thereby raising questions about the findings from stable isotope paleoaltimetry (Schmidt et al., 2023).…”

“…Based on the contemporary disjunct distributional patterns and molecular phylogeny of mega‐diverse Carabus ground beetles, a model of the paleoenvironmental evolution of the HTO has been recently published by Schmidt and colleagues, arguing for a rather young age of cold temperate to alpine biomes in the HTO (Schmidt et al., 2023). This new scenario suggests subtropical or warm temperate environments and, consequently, low average elevations in the orogenetic system until at least the Oligocene‐Miocene boundary.…”

Museomics ofCarabusgiant ground beetles shows an Oligocene origin andin situAlpine diversification

“…14 Ma, Deuve et al 2012) to the early Oligocene (ca. 30 Ma, Schmidt et al 2023). No major improvement in our understanding of Arcifera systematics and evolution has been achieved in the past decade and there is a need to infer a robust evolutionary tree for this section of Carabus to better understand the morphological, ecological, and geographical evolution of constituent lineages.…”