Actual Infinity in Reality?

[Anomalocaris]

Not all of them.  Most of them begin as conceptual model which are then described by mathematics so that their construct are made specific enough for any internal contradictions to be made manifest, or their predictions made precise and thereby possible to verify with precision or falsify.

But you’re saying it is true that they are mathematical models before scientists go out into the physical world to tests them, yeah?

Only with those models constructed with enough attention towards reflecting known and relevant facts that they can not readily be dismissed without careful evaluation.