Incompatibilities in interspecific hybrids, such as sterility and lethality, are widely observed
causes of reproductive isolation and thus contribute to speciation. Because hybrid …

It is now clear that sex chromosomes differ from autosomes in many aspects of genome
biology, such as organization, gene content and gene expression. Moreover, sex linkage …

According to the Dobzhansky–Muller model, hybrid sterility is a consequence of the
independent evolution of related taxa resulting in incompatible genomic interactions of their …

The three fruitfly species of the Drosophila simulans clade—D. simulans, D. mauritiana, and
D. sechellia—have served as important models in speciation genetics for over 40 years …

Studies of a hybrid zone between two house mouse subspecies (Mus musculus musculus
and M. m. domesticus) along with studies using laboratory crosses reveal a large role for the …

Heteromorphic sex chromosomes, where one sex has two different types of sex
chromosomes, face very different evolutionary consequences than do autosomes. Two …

Evolutionary changes in gene expression underlie many aspects of phenotypic diversity
within and among species. Understanding the genetic basis for evolved changes in gene …

When gene regulatory networks diverge between species, their dysfunctional expression in
inter-species hybrid individuals can create genetic incompatibilities that generate the …

The X chromosome has a large effect on hybrid dysfunction, particularly on hybrid male
sterility. Although the evidence for this so-called large-X effect is clear, its molecular causes …

Gene expression has a key role in reproductive isolation, and studies of hybrid gene
expression have identified mechanisms causing hybrid sterility. Here, we review the …