So do you guys remember learning about Lamarck in high school biology class when studying evolution? He’s the giraffe guy. You know, had the theory that giraffe necks got longer over time because they wanted to reach leaves and they gained that from their parents and grandparents and so on. We always laughed at him him and said how stupid he was, saying “Darwin knows what is up and Lamarck is just plain dumb”. Though Darwin was incredibly intelligent beyond belief, there is no reason to shoot down Lamarck because of his theory. It was not correct but it wasn’t totally out there! I would have probably thought the same thing in that day and age too. But anyway, that is not what this post is about exactly. After reading a lot on epigenetics and how what we eat and what we are exposed to becomes “memorized” in our genome (epigenome more specifically), it gets passed on to our offspring, so that must contribute to evolution, right? Lamarck’s theory was that acquired characteristics can become inherited. Though the idea of stretching your neck all day would make your offspring have long necks is wrong, the idea that changes to your epigenome can get passed on is true! (Though remember that epigenetics is not just about inheritance. Most of it involves changes of expression during development. The exact definition of epigenetics is always being debated as well) And changes to your epigenome can occur from eating that hot dog or smoking that cigarette. I mean, we haven’t investigated epigenetics in evolution that much, so this is basically unknown in terms of long periods but when gene expression levels change, the individual produces different amounts and levels of proteins and that changes what the body can do. Maybe Lamarck was onto something (obviously not this specific; genetics was completely unheard of at the time. Even Darwin did not know of it but knew the idea of it).
Anyway, I just thought this was cool and wanted to share. I’m personally more interested in epigenetic mechanisms and their influence on diseases and during early development but I do love evolution and immensely enjoyed the class I took on it last fall. Understanding epigenetic changes over time could be something really interesting to look into. It may be 200 years late, but damn Lamarck, you had the right idea!