In most stork species, males establish themselves on a potential nest site at the start of the breeding season; in Anastomus, Mycteria, and Leptoptilos species the unmated males perform advertising display(s): Display Preening (Mycteria spp.
In Mycteria and Leptoptilos species, the female approaches the male in a Balancing Posture, with the body horizontal, neck partially extended, bill pointed down, and wings spread (Kahl 1966, 1972a,b).
In addition, maximum-parsimony trees resulting from the analysis with all characters given unit weight differed with respect to relationships among the three Leptoptilos species.
These two displays are common and unique to Anastomus, Leptoptilos, and Mycteria species.
The pairing of the genera Leptoptilos and Mycteria is found in one-half of the most-parsimonious trees obtained from analysis of the behavioral data matrix, and this pairing is supported by two characters: presence of the Balancing Posture (character 1) and drooping of the undertail coverts in the Snap Display (character 16).
Surprisingly the vulnerable Lesser Adjutant Leptoptilos
javanicus was unknown from DSNP until breeding was reported in 1995 (8+ nests) and 1996 from the Nung forest, where they had not been breeding for the last thirty years (Dennis et at.