Jumping seeds and galls

Jumping and Non-Jumping Genes

The term ‘horizontal transfer (HT)’ refers to the transfer of genetic material between two reproductively isolated organisms. HT is thought to occur rarely in eukaryotes compared to vertical inheritance, the transmission of DNA from parent to offspring. In a recent study we have provided evidence that a family of DNA transposons, called SPACE INVADERS or SPIN, independently invaded horizontally...

Recombination and peak jumping

We show that genetic recombination can be a powerful mechanism for escaping suboptimal peaks. Recent studies of empirical fitness landscapes reveal complex gene interactions and multiple peaks. However, classical work on recombination largely ignores the effect of complex gene interactions. Briefly, we restrict to fitness landscapes where the global peak is difficult to access. If the optimal g...

Jumping Sequences

An integer sequence a(n) is called a jump sequence if a(1) = 1 and 1 ≤ a(n) < n for n ≥ 2. Such a sequence has the property that ak(n) = a(a(· · · (a(n)) · · · )) goes to 1 in finitely many steps. We call the pattern (n, a(n), a2(n), . . . , al(n) = 1) a jumping pattern from n down to 1. In this paper we look at jumping sequences that are weight minimizing with respect to various weight functio...

Jumping Champions

Fossil oak galls preserve ancient multitrophic interactions.

Trace fossils of insect feeding have contributed substantially to our understanding of the evolution of insect-plant interactions. The most complex phenotypes of herbivory are galls, whose diagnostic morphologies often allow the identification of the gall inducer. Although fossil insect-induced galls over 300Myr old are known, most are two-dimensional impressions lacking adequate morphological ...