Score One For Lamarck

Acquired traits passed on to descendants:

“In our study, roundworms that developed resistance to a virus were able to pass along that immunity to their progeny for many consecutive generations,” reported lead author Oded Rechavi, PhD, associate research scientist in biochemistry and molecular biophysics at CUMC. “The immunity was transferred in the form of small viral-silencing agents called viRNAs, working independently of the organism’s genome.”

An interesting theoretical explanation:

According to the CUMC researchers, Lamarckian inheritance may provide adaptive advantages to an animal. “Sometimes, it is beneficial for an organism to not have a gene expressed,” explained Dr. Hobert. “The classic, Darwinian way this occurs is through a mutation, so that the gene is silenced either in every cell or in specific cell types in subsequent generations. While this is obviously happening a lot, one can envision scenarios in which it may be more advantageous for an organism to hold onto that gene and pass on the ability to silence the gene only when challenged with a specific threat. Our study demonstrates that this can be done in a completely new way: through the transmission of extrachromosomal information. The beauty of this approach is that it’s reversible.”

Beanie bow:  Courtney Conklin Knapp