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Sure. I'll give you an example from one of my kids books that I had discussed in an earlier thread:

"Biology- Understanding Life" – Alters & Alters - copyright 2006.

As always, I no more than flipped it open to page 251 where a new chapter starts and am immediately drawn to strange claim made in the first paragraph. The chapter is titled “Beyond Darwinism: A Genetic Basis of Evolution.” The very first sentence in the chapter says “Scientists know that snakes evolved from ancient lizards.”

They know this ?? The next two paragraphs go on to explain the hypotheses that have been formed to explain how the ancient lizard lost its legs. Now, I have heard that there is supposedly fossil evidence to suggest that snakes evolved from lizards but to see a college level text declaring that scientists KNOW this is, to me, a good example of the dishonest claims that are often made.

And then you have this:
"Houssaye, however, does not think the case is yet closed as to whether or not snakes evolved from a marine or land-based lizard.
"The question of snake origin should not be resolved in the next 10 years," Houssaye said.
She is, however, hopeful that all of the separate teams working on this puzzle can one day pinpoint what species was the common ancestor of all snakes."  http://www.msnbc.msn.com/id/41463087/ns/technology_and_science-science/   February 7, 2011

This “story” (when examined carefully) claims that these alleged useless hind legs were present on this poor creature for anywhere from 4million to 22 million years !!! Was it a land based lizrd or a marine based lizard ? Don't know.  Not only that, this “snake” expert (or whatever she is) openly admits that the fossil record cannot pinpoint an ancestor.

But my kid’s biology book says that scientists know that snakes evolved from lizards. Nice.
You do realize that scientists never know anything with 100% certainty, don't you?  That means that Dr. Houssaye - who by the way is a paleontologist, thus why she's studying fossilized snakes - was saying that we don't know the exact fossil record of snakes very well yet.  However, that does not mean that scientists are not reasonably certain[1] that snakes are descended from lizards.  That's because scientists do not rely on one single source of knowledge.  Morphology, phylogeny, biochemistry, and genetics all point at snakes having a common ancestor in the lizard family somewhere.  We just don't know for sure which one it is, thus Dr. Houssave's comments.

While I'll grant that textbook manufacturers are not always very good at putting things the way scientists would put them, to pick something like this - a textbook saying that scientists knowing something, then trying to make the case that they don't know because all the holes haven't been filled in yet - as your example seems more than a bit ludicrous.  Honestly, it comes across as you trying to find excuses to justify what you already believe.
 1. close enough to say they know
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median HAHA! Yep there it is. January 26, 2014, 10:49:01 AM