Life history theory has become a prominent framework in the evolutionary social sciences,
and the concept of trade-offs, the cornerstone of life history theory in studies on non-human …

In this article we show that the population of Serengeti Masai giraffes Giraffa camelopardalis
tippelskirchi is extremely female biased, particularly among newborns. Our results suggest …

Adaptive adjustments in offspring sex ratios in mammals have long been reported, but the
conditions and mechanisms that prompt shifts in the proportion of sons and daughters born …

A major component of sex‐allocation theory, the Trivers–Willard model (TWM), posits that
sons and daughters are differentially affected by variation in the rearing environment. In …

Recent research has found empirical evidence in support of the Trivers-Willard Hypothesis
that offspring sex allocation is correlated with maternal investment. Tammar wallabies …

The main component of mammalian maternal care is milk production. The composition of
milk has been hypothesized to determine offspring survival, and to vary with offspring sex …

Across animal taxa, reproductive success is generally more variable and more strongly
dependent upon body condition for males than for females; in such cases, parents able to …

When resources are limited, organisms face allocation conflicts. Indeterminate growth
creates a persistent conflict with reproduction, as growth may enhance future reproduction …

Reproduction can lead to a trade-off with growth, particularly when individuals reproduce
before completing body growth. Kangaroos have indeterminate growth and may always face …

Brood sex ratios (BSRs) have often been found to be nonrandom in respect of parental and
environmental quality, and many hypotheses suggest that nonrandom sex ratios can be …