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DEATH IF NO PARASITE IN HOST. “Cytoplasmic incompatibility is a selfish reproductive manipulation induced by the endosymbiont Wolbachia in arthropods. In males Wolbachia modifies sperm, leading to embryonic mortality in crosses with Wolbachia-free females.” https://lnkd.in/dXjWp9f View in LinkedIn

THE STAR of this series is a bacteria called Wolbachia. “It is one of the most common parasitic microbes and is possibly the most common reproductive parasite in the biosphere. Its interactions with its hosts are often complex, and in some cases have evolved to be mutualistic rather than parasitic. Some host species cannot reproduce, or even survive, without Wolbachia colonisation. One study concluded that more than 16% of neotropical insect species carry bacteria of this genus, and as many as 25 to 70% of all insect species are estimated to be potential hosts.” https://lnkd.in/dZe2vg8 View in LinkedIn

FRAGMENT FROM NATURE for this and next weekend focuses on a bacterial parasite which has evolved an extraordinary proliferation strategy: make only infected hosts able to reproduce. The article is titled: Life and Death of Selfish Genes: Comparative Genomics Reveals the Dynamic Evolution of Cytoplasmic Incompatibility. https://lnkd.in/dXjWp9f View in LinkedIn

Yes, as it seems. This is his habit. Lucky me. View in LinkedIn

TWO AUTHORS. “The design of our bodies is simultaneously extraordinarily precise and unbelievably slipshod. It is as if the best engineers in the universe took every seventh day off and turned the work over to bumbling amateurs.” (Randolph Nesse and George Williams) https://lnkd.in/d9KtiYn View in LinkedIn

THE REMNANT. “The evaporation of the black hole plausibly continues until an advanced time at which there are no longer any trapped surfaces for z < 0 . If evaporation were to stop sooner, the result would be a "dead" remnant black hole containing all the quantum information of the Hawking "partners." https://lnkd.in/dUKnus8 View in LinkedIn

PROBLEM. “Numerical calculations of the renormalized semi-classical stress-energy tensor outside the horizon of a Schwarzschild black show a flow of negative energy into the black hole starting a finite distance outside the horizon, and are inconsistent with an outflow of positive energy Hawking radiation from pair creation or tunneling very close to the horizon.” https://lnkd.in/dUKnus8 View in LinkedIn

ASSUMPTIONS. “The model assumes spherical symmetry of the geometry, which, while the black hole is large, is extremely close to Schwarzschild near and outside of the black hole horizon.” https://lnkd.in/dUKnus8 View in LinkedIn

REPERCUSSIONS. “This has implications for the validity of the generalized second law and certain quantum singularity theorems as applied to black holes.” https://lnkd.in/dUKnus8 View in LinkedIn