Most mainstream paleontologists and geologists place dinosaurs on earth’s timeline at around 220 million and 65 million years ago, during the Mesozoic Era. Homo sapiens on the other hand, do not appear in the record until about 200,000 years ago - in the Middle Pleistocene, Middle Paleolithic (Eurasia), or Middle Stone Age (Africa).
Prokaryotes constitute the majority of sedimentary biomass, where they cycle organic carbon and regulate organic matter transformation. The microbes inhabiting sediment are diverse, and the factors controlling microbial community composition are not fully understood. Here, we characterized the prokaryotic community using 16S rRNA gene sequencing in 24 stratigraphic layers within a 89 cm (dated to ~1900 years old) sediment core from an anchialine sinkhole in the Bahamas with a stratified water column and anoxic bottom water. The microbial community was dominated by members of the Alphaproteobacteria, Dehalococcoidia, Gammaproteobacteria, Bathyarchaeota, and Campylobacter classes. Most interestingly, subsurface microbial community structure could be correlated to previous evidence for timewise changes in the main source of organic matter that was supplied to the sediment accumulating during the last 2000 years, which itself was caused by regional terrestrial vegetation changes. The C:N r
The Beauty of Early Life. Traces of Early Life invites us to look at the emergence of life through artistic works from modern times to the present, complemented by scientific exhibits from the early days of life.
South Africa’s Cradle of Humankind was home to five early hominins, and it continues to yield new finds related to the earliest stages of human evolution.
A landmark art exhibition at the University of the Witwatersrand Art Museum (WAM) Johannesburg, celebrates a brilliant indigenous artistic arc: the timely exhibition Seen, Heard and Valued pays tribute to 40 years of indigenous collecting and academic research.South Afri.