Pollen taphonomy from hyaena scats and coprolites: preservation and quantitative differences

Abstract

Coprolites are often used in African archaeological sites as archives for proxies like pollen, which are trapped and preserved inside them. Investigating pollen taphonomy, here we aim to aid interpretations of local and regional vegetation changes by assessing dietary and other pollen sources of fresh hyaena scats from the Tswalu Kalahari Reserve (TKR, South Africa) and coprolites from Equus Cave (South Africa). Our hypothesis is that the inner and outer fractions of coprolites possibly reflect qualitative and quantitative differences of dispersal factors of pollen taxa during the stages of scat formation influenced by hyaena behaviour and pollen sticking to wet surfaces after defecation. We mechanically separated the inner and outer sections of each scat and coprolite and extracted pollen from both fractions for analyses. The results were associated with vegetation maps of TKR and compared with pollen in modern soils, as controls, and quantitatively analysed in order to test potential differences in quality and richness of pollen between the inner and outer parts of samples. Scats and coprolites seem to be less biased sensors of vegetation than surface soil samples. Further, the inner parts of coprolites and scats provide significantly greater diversity of low pollen-producers including entomophilous types than the outer sections which may typically be biased by wind-transported types and less productive due to pollen loss by weathering. The core fraction might therefore be useful for representing the under-represented taxa in pollen assemblages from the surroundings where hyenas roam.