I searched “Sandor at the Zoo” because vanity, and I noticed (slightly above this blog), the wikipedia page for Henry Spencer. Which does not contain the word “sandor” anywhere on it, and the only instances of the word “zoo” are “utzoo” and “zoology.”
The small size of Usenet in its youthful days, and Spencer’s early involvement, made him a well-recognised participant; this is commemorated in Vernor Vinge’s 1992 novel A Fire Upon the Deep. The novel featured an interstellar communications medium remarkably similar to Usenet, down to the author including spurious message headers; one of the characters who appeared solely through postings to this was modeled on Spencer (and, slightly obliquely, named for him).
I suppose that it is likely that some other pages discuss the origin of the “Sandor at the Zoo” character in A Fire Upon the Deep, and mention Henry Spencer. I suppose it is unlikely that Google’s search algorithm actually managed to infer that the above passage referred to “Sandor at the Zoo.” But it sure seems like magic.
(I did not know about Spencer until now.)