And all of them are currently "good enough", so roughly at the same level of fitness. Of course, models that have been relatively stable for 400M years, like sharks, are in some sense "better" than the fad of the day, like us.

"good" shouldnt be conflated with "most evolved."

To be more evolved, means to be more changed from the source. It means specialization for a specific scenario. Often "more evolved" can be "worse" once the environment changes, and that specialization becomes a disadvantage instead of an advantage. Or that a change brings one benefit but another potentially larger pitfall in the long run.

The amount of evolution should be measured in iteration cycles, how much change over how much time. It's also possible that something iterated many many times quickly long in the past and then stopped, vs something that just started making changes more recently.

>We are last in the sense that we are leaf nodes on the tree of life (at least for the moment

Who said that? There are tons of newer than us leafs (organisms that evolved after we did).

If you mean "but there are no futher evolved human ancestors", that's not an exception: that's the same case with almost all current animals.

I think you misunderstood parent. There is a natural order on the tree of life starting in the first living organism (the root node) and ending in organisms that are still around (the leaf nodes).

With 'last' parent meant 'last with respect to that order', not necessarily in the sense of 'older' and 'newer' (which correlates with this order, as you pointed out).

> Who said that? There are tons of newer than us leafs (organisms that evolved after we did).

I meant leaf nodes in the sense of the tree data structure, so I think we are saying exactly the same thing.

> If you mean "but there are no futher evolved human ancestors", that's not an exception: that's the same case with almost all current animals.

Yes that's exactly what I meant with the second part of my comment.