MARYLAND   SLAVE  POPULATION

45

chances of survival beyond infancy and childhood.44 A similar decline
in black mortality would help explain the increase in the proportion of
children in the slave population.

There are several reasons to assume an increase in the number of
births in the 17205, all associated with a growing number of native-born
women in Maryland's slave population. The slaves who arrived in the
four counties during the seventeenth century did not fully reproduce them-
selves, but they did have some children. By the 17205 natives must have
formed a demographically significant proportion of the black population.
Perhaps in part because of differences in attitude (presumably, natives
were more thoroughly assimilated and less alienated than immigrants45),
but primarily because their reproductive life in the colony was longer,
native women bore more children in Maryland than did their immigrant
mothers.

African-born slaves in the New World, Curtin has noted, were "sub-
ject to the epidemiological factors that affect all people who move from
one disease environment to another. Most important immunities to
disease are acquired in childhood. To move into a new disease environ-
ment as an adult normally exacts some price in higher rates of morbidity
and mortality among the immigrants." As a result, Curtin suggests,
African-born slaves died younger and were more often sickly than
Creoles.48 Studies of adult expectation of life demonstrate that native-born
white men suffered less from chronic ill-health and lived longer than
their immigrant parents. Improved health and longevity among native-
born black women would result in an extension of the average repro-
ductive life and a rise in the number of births per woman. However,
among white males in the seventeenth century, the expectation of life
at age 20 was only slightly longer for natives than for immigrants.47 If
the experience of black women was similar to that of white males, im-
provements in health and longevity are not, by themselves, a sufficient
explanation of the increase in the child-woman ratio.

An analogy with Europeans in the Chesapeake suggests not only that
the reproductive years were extended by longer expectation of life for

44Walsh and Menard, "Death in the Chesapeake," Md. Hist. Mag., LXIX (1974),
218-219.

45 Mullin, Flight and Rebellion, passim.

40 Curtin, Atlantic Slave Trade, 19; Curtin, "Epidemiology and the Slave Trade,"
PSQ, LXXXIII (1968), 190-216.

4T Walsh and Menard, "Death in the Chesapeake," Md. Hist. Mag., LXIX
(1974), 218-219.