The appropriate balance of antagonism of the two receptors for sleep is a point of debate, although in rodent models OX2R antagonism alone appears sufficient to induce sleep, whereas OX1R antagonism is largely devoid of this effect.
This would then imply that in natural populations, variation is regulated by sets of genes, which balance conditional antagonism and general fitness (Olson-Manning et al. 2012).
The wall serves as the symbolic fulcrum of their friendly antagonism; it balances their contrasting philosophies about brotherhood, represented by the sentiments "Good fences make good neighbors" and "Something there is that doesn't love a wall".
If sexual antagonism is resolved through the evolution of optimal sexual dimorphism, or if the strength of selection in the two sexes is balanced, there is no longer an expectation that one allele at a locus will produce higher fitness outcomes than the other.
Rather, it wishes to "re-balance" the region's major powers -- to strike an equilibrium of antagonisms -- and wishes them to sort issues out amongst themselves.
She writes thoughtfully about the erotic antagonism in the muse/artist relationship, the anxiety of growing up in the shadow of success, the agony of balancing professional ambition and domestic commitment.
One reason may be that people tend to prefer symmetry in their relationships, balance in their shared antagonism just as in their shared affection.
Due to the somewhat contrasting antidepressant-like properties of 5-HT1B receptor agonism and memory deficit-reducing effect of 5-HT1B receptor antagonism, a balance of stimulation versus blockade of this receptor may be needed.
Thus, a proper balance harmonizes the roots and banishes antagonism.
The trophectoderm lineage arises from the balance between Oct4 and Cdx2 through mutual antagonism; an excess of Cdx2 gives rise to the trophectoderm lineage, whereas an excess of Oct4 results in the stem cell state [12].
