The rapid generation of new shapes observed in the living world is the result of genetic variation, especially in “morphological” developmental genes. Many of these genes contain coding tandem repeats. Fondon and Garner have shown that expansions and contractions of these repeats are associated with the great diversity of morphologies observed in the domestic dog, Canis familiaris.1 In particular, they found that the repeat variations in two genes were significantly associated with changes in limb and skull morphology. These results open (...) the possibility that such a mechanism contributes to the diversity of life. BioEssays 27:581–587, 2005. © 2005 Wiley Periodicals, Inc. (shrink)

With the ever‐increasing lifespan along with societal changes, women can marry and procreate later than in previous centuries. However, pathogenic genetic variants segregating in the population can lead to female subfertility or infertility well before the average age of normal menopause, leading to counter‐selection of such deleterious alleles. In reviewing this field, we speculate that a logical consequence would be the later occurrence of menopause and the extension of women's reproductive lifespan. We illustrate this point with a simple model that (...) applies to other variants that contribute to female infertility, including epigenetic variation. We also consider the effect of medical interventions and lifestyle. (shrink)