CATEGORIES OF PARENTAL BEHAVIOR 
The various categories of parental behavior, as reported in the 
literature, are listed below. The symbol in parentheses identifies the 
categories used in Tables I and II. The literature sources are provided in 
Tables V and VI. 
Coil around brood (C): The attendant parent remains coiled around or covers 
the brood with its body, presumably creating a physical buffer or barrier 
between progeny and the external environment. This is the most common form of 
parental behavior. 
Nest constructed and maintained (NC): A burrow or brood chamber is 
constructed by the parent and maintained while attending progeny. Although 
this usually involves digging a depression or burrow in the substrate, 
Ophiophagus hannah is known to maintain a relatively complex nest chamber 
constructed from surrounding vegetation (Wasey, 1892; Oliver,1956; Leakey, 
1969; Whitaker, 1977). 
Defense of brood (D): Progeny are aggressively defended by parent in the 
presence of conspecifics or heterospecifics. 
Passive protection (PP): Neonatal vipers may accrue protection from the 
venomous female, without her exhibiting any overt signs of aggressive behavior 
(i.e., Crotalus horridus: W. Martin, pers. comm.). 
Thermoregulation (T): Attendant parent uses its body to maintain a relatively 
constant incubation temperature for developing eggs. Most, perhaps all, 
pythonines are able to become low-grade endotherms while brooding through 
"shivering thermogenesis," thereby raising the temperature of the female's 
body and developing eggs above that of ambient conditions (Vinegar et al., 
1970; Harlow and Grigg, 1984; Shine, 1988). However, it has been suggested 
that shivering thermogenesis is not practiced by all species of pythons 
(Vinegar et al., 1970; Ellis and Chappell, 1987; but see [Orlov], 1986; Shine, 
1988). It is also possible that an attendant parent could (1) provide a 
passive thermal barrier between eggs and the external environment with its 
body or (2) bask in the sun and transfer radiantly absorbed heat from its body 
to its eggs (Medsger, 1919, 1932; Noble and Mason, 1933; Cogger and Holmes, 
1960). Python eggs, of at least two species, that are not brooded, and 
subsequently incubated at lower temperatures, take longer to hatch and exhibit 
a higher rate of developmental anomalies (Vinegar, 1973, 1974; Branch and 
Patterson, 1975). 
Hydroregulation (H): Even though is has never been demonstrated 
experimentally, hydroregulation has been inferred from some squamates (Fitch, 
1954; Somma, 1985b; Bels and Van den Sande, 1986; [Orlov], 1986; York and 
Burghardt, 1988; Somma, 1989b; Somma and Fawcett, 1989). In addition, tenuous 
evidence suggests that two species of snakes wet their bodies with water and 
then lay over the eggs, thereby reducing desiccation (Elaphe obsoleta: J. 
Lombard, pers. comm.; Trimeresurus wiroti: Mehrtens, 1987). 
