- Thu Jul 27, 2017 4:46 pm
#37720
Hi brcibake!
This passage is about Lamarack's "hypothesis"--his claim "that an animal’s use or disuse of an organ affected that organ’s development in the animal’s offspring," like a giraffe's neck developing from its need to stretch, and passing to its offspring. This claim hadn't been proven for centuries since Lamarack proposed it, in large part because it wasn't clear what mechanism would allow this to happen.
However, the author of the passage notes new evidence that supports Lamarack's hypothesis. More specifically, the author goes on to mention examples--including cell walls of bacteria, viruses, fruit flies, and E. coli--that involve an acquired characteristic being passed on via reproduction. The author goes on to clarify the difference between "vertical" and "horizontal" inheritance, and then concludes, "Such horizontal transmission may well be the mechanism for inheritance of acquired characteristics that has long eluded biologists, and that may eventually prove Lamarck’s hypothesis to be correct."
Hope that helps!
