Upon postulations of the now terminal demise of biodiversity presently occurring: similarly to during the end of the Pleistocene-Cretaceous period; is the resultant corollary absence of an essential perpetuating nature for viability, via this requisite derivated quality of ecology, then when destroyed potentially fatal to the continuum of human viability on earth or then as causal of surviveability even being definitive as a function of said biodiversity, ecological integrity, a living and integrated biosphere, or any ideation of a “web of life”; and, if so, why?

Reiterating; are integral biogenetic systems, with particular ecological biometric definitions, stipulated as having been proven vital theory for sapiens’ perpetuation; even if only in civil habitats on earth?

If not, and then if squandered, poisoned, shattered and destroyed; can an alternate maintenance of particularly a principle inter species bio-integrity remaining in the biosphere (with modalities of biodiversity doomed) then be causal of a functional avoidance of drastically increasing mortality rates amongst human populations now beginning to rapidly surpass the earthly presence of perhaps approximately ten billion souls?

Human populations are typically found inside regional urban limitrophes and in various proximity to wildernesses and natural resources producing lands of various primarily USA/Soviet/CCP era infrastructural paradigm designs and implementation histories.