 And if you think penetrance is weird, then you have to look at the environment. Now, for a long time, we thought that the environment does not affect heredity, and we're learning that that is just crazy. My first example is that the environment can affect the phenotype without influencing heredity, and that is the example of the hydrangeas here. I don't know if you have hydrangeas, there's a lot of them around Humboldt County, but I can't remember which is which, but hydrangeas that are growing in acidic soil, I want to say acidic soil makes blue hydrangeas. It's the environment. It's the pH of the soil that results in blue flowers. Hydrangeas that are grown in basic soil get pink flowers, and it's the pH of the soil, it's the environment. It isn't a genetic condition, and this is going to mess things up, because you would look at the hydrangea flowers and be like, oh, clearly these are two different genetic variations of the hydrangea until you did clones and planted them in different pH soils and then realized, no, actually, this is an environmental effect on phenotype. We always thought that environmental phenotypic, what, issues, I guess, or demonstrations, we always thought that those environmental things were not heritable. We are learning that there are some environmental conditions that we expose ourselves to and that literally are changing our DNA and that those DNA changes that are happening are passed on to our babies. That is crazy talk, and that's a whole layer of research. It's called epigenetics, and the study of epigenetics, epi meaning above the genome. So we've been focusing in on the genome and these are the proteins that are coded for, but then there's this whole layering of regulating factors that affect the genome, that regulate it, that turn things on and off and our environment will, what we expose our DNA to will affect our genes and we pass those on to our kids, which, again, like I said, this is not something that we were originally comfortable with. So we have another example here of this little cutie-cute. This is a little Himalayan bunny rabbit and this bunny rabbit has a protein that's temperature sensitive and the cooler the environment, the browner the protein expresses itself. So cool areas on little bunny rabbit, the very cold nose or the tips of the ears or the tail, these areas express this brown protein pigment, whereas if the little bunny is warm, then it doesn't express that same pigment. And again, that's an environmental impact on the phenotype that in this case isn't genetic. You could actually strap an ice pack to this little buddy boy and make an imprint of the ice pack shape as the new hair grew out over time. So you could cool a part of the body down to the temperature of the ears and the nose and the feet and the tail and like you could draw pictures on your bunny rabbit. It might be kind of mean because he'd be cold. So don't do that. That's not very nice. There's something else I was going to say about my little bunny rabbit. It's gone. It's gone. This lecture is done. Wow. I feel like I'm going to give you a little pep talk really fast. This lecture was a quick lecture, but I think that there are a lot of concepts here that are easy to get confused. So please take some time to really flesh out distinction study. Take some time to study this because you will be happy if you do. Study every day. I will see you. The next lecture is the best whatever. Okay. I can't wait to get started on that one. Bye-bye.