https://www.reddit.com/r/cats/ - 8.4m
https://www.reddit.com/r/dogs/ - 2.8m
https://www.reddit.com/r/catfree/ - 6k
https://www.reddit.com/r/Dogfree/ - 73k

Reddit has a strong pro-cat anti-dog bias. HUGE anti-dog bias. I'd even go as far to say: hating dogs is reddit.

>>5003626
https://www.reddit.com/r/AnomalocarisFans/ - 731
https://www.reddit.com/r/trilobites/ - 1.2k
Reddit strongly prefers trilobites to anomalocaris. QED: Trilobites are reddit. Anomalocaris is 4chan.