Outsourcing to fungal partners is a pretty ancient adaptation (there has to be a review called something like ‘mycorrhizas in land plants’; if you are not able to find it, I’ll track the link later. Contains an interesting discussion of its evolution and secondary loss in some families, like Cruciferae (Brassicaceae)). BTW, it is interesting to note that Ophioglossaceae (a family of ferns, of which Wiki will tell you better than I) are thought to radiate in approximately the same time—and you will see just how closely their life forms resemble orchids! (Er. People who love orchids tend to praise other plants on the scale of orchid-likeness, so take this with a grain of salt.)
I mostly pointed you to the article because it contains speculations about what drove their adaptations in the beginning; I think that having a rather novel type of mycorrhiza, along with the power of pollinators (and let’s not forget the deceiving species!) might be two other prominent factors, besides sheer seed quantity, to spur them onward.
Outsourcing to fungal partners is a pretty ancient adaptation (there has to be a review called something like ‘mycorrhizas in land plants’; if you are not able to find it, I’ll track the link later. Contains an interesting discussion of its evolution and secondary loss in some families, like Cruciferae (Brassicaceae)). BTW, it is interesting to note that Ophioglossaceae (a family of ferns, of which Wiki will tell you better than I) are thought to radiate in approximately the same time—and you will see just how closely their life forms resemble orchids! (Er. People who love orchids tend to praise other plants on the scale of orchid-likeness, so take this with a grain of salt.)
I mostly pointed you to the article because it contains speculations about what drove their adaptations in the beginning; I think that having a rather novel type of mycorrhiza, along with the power of pollinators (and let’s not forget the deceiving species!) might be two other prominent factors, besides sheer seed quantity, to spur them onward.