In the case of the bombina frogs given in your text, there was evidence of hybridization because b. variegata (yellow-bellied toads) genes were present in the b. bombina (fire-bellied toads) in the hybrid zone but the frequency decreased across the hybrid zone with distance from the yellow-bellied toad range. what was the evidence that hybrid zone stability was occurring? in the case of the bombina frogs given in your text, there was evidence of hybridization because b. variegata (yellow-bellied toads) genes were present in the b. bombina (fire-bellied toads) in the hybrid zone but the frequency decreased across the hybrid zone with distance from the yellow-bellied toad range. what was the evidence that hybrid zone stability was occurring?

In the case of the Bombina frogs, the evidence that hybrid zone stability is occurring was the consistent pattern from annual to annual of declining frequency of yellow-bellied toad alleles with distance from the edge of their range. This is a clear evidence that hybridization is taking place yearly in the Bombina frogs.

On account of the Bombina frogs, the proof that half and half zone.  

Explanation:

strength is happening was the steady example from yearly to yearly of declining  recurrence of yellow-bellied frog alleles with separation from the edge of their  extend. This is an unmistakable proof that hybridization is occurring yearly in  the Bombina frogs.orbital hybridisation is the idea of blending nuclear orbitals into new half and half orbitals appropriate for the matching of electrons to shape synthetic bonds in valence bond hypothesis.

oxygen +1 most likely