1/n “..There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity,

2…from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.” Charles Darwin. His (and Alfred Russel Wallace’s) field observations transformed our understanding.(They were big-data scientists, ahead of their time).Pix BennyShilo

3… As did the ‘laboratory’ small-science of Gregor Mendel and subsequent geneticists; and the work of embryologists such as Hans Speman and Hilde Mangold and physiologists such as Alan Hodgkin and Andrew Huxley. Pix Speman and Mangold

4 As Sydney Brenner put it, biologists ask only three questions. Where does it come from (evolution)? How does it work (physiology)? ; and how is it made (developmental biology)?
Pix @Archives_NCBS

5 Evolution is very relevant today! If we want to know how and why bats harbour viruses, which can spread to humans, we must ensure, and enable, speedy and quality research into Brenner’s three questions.

6 This recent paper in @eLife https://elifesciences.org/articles/48401  tells us how, perhaps, bats harbour viruses which can cause serious disease in humans, while bats themselves are resistant. Quotes from the abstract below.

7 “Bats host virulent zoonotic viruses without experiencing the disease. A mechanistic understanding of the impact of bats' virus hosting capacities… is needed to elucidate zoonotic emergence. “

8 The authors carried out “virus infectivity assays on bat cell lines..” In which the immune system was inducible or modified, then developed a theoretical model to fit data. (Look at the author list and their expertise!)

9 The model supported the view that there are “robust antiviral defences in bat cells that correlated with higher estimates for within-host viral propagation rates”

10 In general, the suggestion is that the bats' heightened immune responses limit the virus’s ability to affect cell function. This in turn “can facilitate the establishment of rapidly-propagating persistent infections” within bats.

11 “Rapidly-replicating viruses that have evolved with bat immune systems will likely cause enhanced virulence following emergence into secondary hosts with immune systems that diverge from those unique to bats.”

12/12 Happy (Belated) Darwin day. Pix Benny Shilo from the Galapagos.