What does the word "tiddlers" mean as used below?

" "Although we do not yet have the
capability to detect 'tiddlers' like the Earth, we
can establish theoretically which of the
exoplanetary systems are most likely to have an
'Earth'," said Professor Barrie Jones of The
Open University. "

Edit: I found this, in a site about a Dylan Thomas work. Does then "tiddlers" mean Earth
is a "little fish" as planets go?

Main Entry:tid£dler
Pronunciation:*ti-d*l-*r, *tid-l*r
Function:noun
Etymology:probably from English dialect tiddly little
Date:1885

British : a small fish (as a stickleback or minnow)


Tiddler is used for anything small.

Toddlers are tiddlers, but they're still big fish swimming about in their little bowls. Heaven knows my Loftan was a very big fish in the bowl of my heart as a toddler.