Monday, December 27, 2010

What is Life? Evolution from invertebrates to vertebrates 1(無脊椎動物から脊椎動物への進化その1)

Good morning everyone. Have you submitted your article for your University? Your boss may be busy to re-check your paper. Most professor have no holiday in winter, because it is the one's duty. So please understand the one's status at least in these days.


Here, today's theme is the evolution from invertebrates to vertebrates. Because the origin of Sammy's research history is developmental biology, I want to show an attractive story for you. And I have to apologize you about recent contents. Those articles might be dull for you, because the theme were friends, love, and life. So I would like to treat more biological theme not a spiritual things.


To make you understand evolutionary story, Sammy may have to introduce something base of developmental biology. By such reason, this theme will not end in one or two times. Are you ready?


(1) Classification of animal
We human being has a backbone in our back. It is shared in birds, lizards (reptile), frogs (amphibia), and fishes. Such groups are called as vertebrates. Most people may think that all animals are divided into two classes vertebrates and invertebrates. Of course it is true in a kind of narrow range. But in widely view, most animals are divided into Protostomia and Deuterostomia. We human being belongs into Deuterostomia. On the other hand, insects, clam, octopus are belong into Protostomia. This is a basic of developmental biology.


(2) What is vertebrates?
As described above, we have a backbone. The backbone is also called as spinal cord by histologists. We vertebrates have central nervous system and brain in our head. So we can analyze information, signal, and alteration of surrounding at highly level. However, in strictly speaking, the vertebrates is very unique group. Most animals containing most of Protostomia and primitive groups of Deutrostomia undergo Metamorphosis in their development from juvenile to adult. By such reason, the evolution from invertebrates to vertebrates is one of the most attractive theme for biologists.


Today's class is over. Have a nice day. Click the button at the bottom of this "What is Life?", if you are a student of this class. Mind you? If you have any question about life, please send an e-mail for me.


にほんブログ村 科学ブログ 生物学・生物科学へ人気ブログランキングへ



  1. 無脊椎から脊椎への進化。

  2. Thank you Aya. This theme is little hard to explain easily. But I am an expert of this class. So please look forward to the next.

    Have a happy new year!

  3. Oops don't forget to click the banner when you attend to the class. Ok?


Thank you!