Daily Archives: April 3, 2008

Quote

“In the transmission of human culture, people always attempt to replicate, to pass on to the next generation the skills and values of the parents, but the attempt always fails because cultural transmission is geared to learning, not DNA.”-Gregory Bateson

Giardia: Protozoan of never ending wonders

i-e499dbe326e9df357fe96d52516a27ca-giardia.gif… well, OK, maybe that is a slight exaggeration.You know about giardia. Giardia intestinalis. It causes a nasty gut infection, and you get it by drinking water pretty much anywhere in the US (potentially). It is very hard to get rid of.Giardia adapt to immune system attacks (of their host) in a way that passes that adaptation down to their offspring without genes. It is a Lamarkian process. Giardia have no mitochondria, yet many of the genes known to be in mitochondria in eukaryotes are found in the giardian nucleus. So, ancestral giardia probably had mitochondria, but all those genes got transferred over to the nucleus.The absence of mitochondria and the significant reduction of some other organelles has led people to, probably falsely, believe that giardia is some kind of intermediate between prokaryotes and eukaryotes. Again, this is probably a misinterpretation. Giardia, as a eukaryote which has lost specific organelles (yet still does just fine) would be in a sense “more evolved” than any eukaryote. Including, dear reader, you.And now, there is even a newer twist to the story. Continue reading Giardia: Protozoan of never ending wonders

Dave Eggers: 2008 TED Prize wish: Once Upon a School

Accepting his 2008 TED Prize, author Dave Eggers asks the TED community to personally, creatively engage with local public schools. With spellbinding eagerness, he talks about how his 826 Valencia tutoring center inspired others around the world to open their own volunteer-driven, wildly creative writing labs. But you don’t need to go that far, he reminds us — it’s as simple as asking a teacher “How can I help?” He asks that we share our own volunteering stories at his new website, Once Upon a School. Continue reading Dave Eggers: 2008 TED Prize wish: Once Upon a School