- Joined
- Mar 8, 2004
- Messages
- 4,883
octokidwriter;126332 said:thanks Monty for the very clear answers. They are very useful. Soon you'll all be writing my books for me
They are in fact two books, i am writing the easiest one now, to get me warmed up for the difficult work. you certainly deserve a copy by now, though it will be Dutch to you, I'm afraid!
got another one: three hearts, any idea why?
Why not?
The role of the 3 hearts is actually pretty similar to the two halves of our own hearts. In humans, the left side pumps blood to the body, while the right cycles blood through the lungs to pick up oxygen. In cephs, the main "systemic" heart pumps blood to the body, while the smaller "brachial" heart at each of the two gills pumps through the gills to get oxygen into the blood. So in some sense, it's just moving things around a bit, but essentially working the same way as many other animals that have an active lifestyle that needs to be able to extract oxygen quickly and efficiently.