Talk:1211: Birds and Dinosaurs

Explain xkcd: It's 'cause you're dumb.
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I'm very confused by this article, for the following reasons: 1. The math is blatantly incorrect in this comic. Saurischians/Ornithischians diverged around 230 mya (wikipedia has good sources on this), while we can date the oldest Tyrannosauroids (present after the split between T. rex and the first birds) at around 160 mya (same). Adding in Stegosaurus at 155 mya, T. rex at 65 mya, and Sparrows at 0 mya, we get 255 mya of distance between Tyrannosaurus/modern birds but only 240 mya of distance between Tyrannosaurus/Stegosaurus. This comic would be true if Stegosaurus were replaced by Triceratops, but as it stands Randall seems to be getting the argument incorrect, and I'm not sure why that's not in the description of this article. 2. For some reason the article explanation refers to a Science article that's exactly the opposite of what it's described as suggesting; since almost all dinosaurs are likely to have had some feathers (I can replace this with a non-wikipedia source when I have more time), this makes T. rex more similar to other dinosaurs. ~~thunderbeard

I think you might not be doing the right sums. “The phylogenetic distance between two species is an estimate of the amount of time since the most recent common ancestor of both species, in other words the time that each has evolved independently of the other.” https://phylodiversity.net/wcornwell/papers/Vellend_etal_2011_bookchap.pdf So, I think what you should be comparing is (a) the time since the LCA of sparrow and T. rex to the present day and (b) the time since the LCA of T. rex and Stegosaurus to the T. rex; i.e., just the longer branches of the two inverted red Υ’s. AntAllan (talk) 18:56, 14 November 2019 (UTC)
You are probably confused by the naming: birds did not descend from ornithischians but from saurischians. 162.158.89.114 14:59, 3 November 2021 (UTC)

I added the transcript, That was legit enough. 121.54.48.38 06:03, 13 May 2013 (UTC)

So the next question is, how tall is Ryan North? This is such a shout out! : ) 24.193.34.113 (talk) (please sign your comments with ~~~~)
- According to https://what-if.xkcd.com/16/ (Lightning), "paleontologists estimate he stood nearly five meters tall at the shoulder".162.158.38.196 11:33, 21 October 2018 (UTC)

A few minor edits, Made the text "Falco Peregrinus" italic for the lulz. 121.54.48.38 10:34, 13 May 2013 (UTC)

Transcript currently says "...showing that T.Rex came at the same time as sparrows", which isn't what is showed at all (or at least implied, and certainly isn't correct). But I'm not sure about alternate wording of this. Something to do with the common ancestor to both branching much more recently, perhaps, if that isn't already dealt with? 31.110.57.223 12:07, 13 May 2013 (UTC)

Sorry about that, I added the transcript and I was an idiot at the time so I thought "Maybe they came at the same time?", So I just added that, Sorry about that. 121.54.48.38 22:55, 13 May 2013 (UTC)
Quote

So I take it that the last line marks him as a Browncoat? --Thisfox 122.148.216.22 07:20, 13 May 2013 (UTC)

Yes, I believe you will. 121.54.48.38 07:53, 13 May 2013 (UTC)
Diagram

Some evolution diagrams are honest enough to use solid vertical lines for the bits that are actually known and dotted horizontal lines for the wishful thinking bits connecting the different families. 121.74.153.117 00:00, 16 May 2013 (UTC)