Check out the MetaHub article for sure, but I’ll give a brief explanation as well.
Time of day doesn’t change what zone you’re in, but it changes the types of dinosaurs that you’ll see. For example, Velociraptor appears at night and during dawn/dusk. Conversely, Apatosaurus appears during the day and dawn/dusk. Some creatures, like Baryonyx, can be found at any time of the day.
There are three*** main types of spawns in this game: global, zone, and park spawns. Global spawns can appear anywhere. For example, T-Rex is a global day/dawn/dusk spawn. Baryonyx is a global anytime spawn.
Zone spawns (better known as habitat zone spawns) will only appear in a specific habitat zones. There are four habitat zones in all (abbreviated to L1, L2, L3, & L4). For example, you know you’re in habitat zone 1 (L1) if you’re seeing a lot of Deinocheirus and Majungasaurus. If you’re hunting for Epic Monolophosaurus, you know you’re in the right zone for it if you’re seeing Diplocaulus and Allosaurus.
Habitat zones, at best, are anywhere from .5 to 1 sq. kilometer in size…You’ll recognize that you’re in a different habitat zone based on the types of creatures you’re seeing. Sometimes all it takes is crossing a major road to enter a different zone.
Finally, park spawns are…you guessed it…exclusive to parks or green areas on your in-game map. Tanycolagreus, for example, is a park spawn. However, park spawns don’t necessarily spawn in parks—they may also spawn next to green Event Supply Drops, which might be quite far from your nearest park.
***There were nest spawns as well (certain dinosaurs more likely to be found near restaurants, auto repair shops, etc.), but MetaHub didn’t include a chart for this in their latest article, so I’ll leave this be.
Hope this helps!