Hawks om syskonen på alla fyra

published Mar 14, 2006 09:30   by admin ( last modified Mar 14, 2006 09:30 )
Det har varit mycket publicitet kring de syskonen från Turkiet som går omkring på alla fyra. John Hawks har skrivit ett utmärkt inlägg om det, och jämför med Floreshysterin:

Consider: a rare, unique, and strange discovery comes to light. Immediately many experts are skeptical, but it takes time for them to organize a response. In the interim, a few strong backers explain that unique evolutionary principles can explain the find, and some experts cautiously agree. Then, two things happen: first, there is a conflict between the Western backers of the find and a senior local scientist; second, a high-profile documentary appears in which the discoverers can take their case directly to the public.

It's an autocircus.

Hawks tar bl a upp det där med
att genmutationen som verkar finnas hos syskonen skulle vara en slags switch mellan två gångarter:

Cerebellar ataxia breaks a whole lot of things. It's like breaking the crankshaft -- the engine might run, but it is going to make a whole lot of noise, and the car isn't going to move. We may conclude that the crankshaft is necessary for the wheels to move. But does that mean that the crankshaft is the key component of the wheel? Clearly not.

The analogy between cars and organismal development is useful because both systems depend on hierarchical functions. Early things must all work right for later things to develop. When an upstream gene (or part) breaks, it doesn't mean that downstream things affected by the broken gene were caused by the broken gene.