You're right. Astronomy is considered to be the least speculative of the sciences.
And you're right again. There are highly speculative theories in astronomy.
And right a third time. Evolutionary theory is currently a mess. So was astronomy in the time of Kepler and Galileo.
I was trying to say this is really hard stuff. A scientist looks at the new skull and tries to fit it into his existing theories. If he can't he's got to come up with new ones. The only alternative is to throw out the evidence and keep the theories. That's a real loser .
It seems to me though that we built upon the findings of Kepler and Galileo- that there were genuine discoveries in the work of early astromeners even is other of their findings didn't hold up. Evolution is not like that as a theory- it is in utter tatters. And Modern Genetics did much to destroy it.