Climate change can lead to extremophilic endosymbiotic archaeal growth and neanderthalisation of the species. There is increase in endosymbiotic and colonic archaeal growth. The increase in colonic archaeal growth leads to breaching of the blood-gut barrier and archaeal endosymbiosis. The colonic archaea also generates RNA viroids which are converted to DNA viroids by colonic epithelial HERV reverse transcriptase and gets integrated into the human genome. The RNA and DNA viroids hybridise with the viroidal and bacterial population of the gut microbiome and virobiome DNA and RNA of the gut leading to generation of new emerging viruses. The RNA and DNA viroids and gut bacteria can also hybridise with human genomic sequences for immunity, metabolic regulation, growth factors, cell growth, cell death, neurotransmitters and HERV sequences of the colonial epithelial cell. The hybridization of archaeal RNA viroids with human genomic HERV sequences can generate retroviruses and new emerging viruses like Covid 19. This leads to generation of new bacteria, RNA and DNA viruses generating newer pandemics as well as the end of the homo sapien species and the world by global warming.