Short interspersed nuclear elements (SINEs), one category of the transposons, are widely distributed in eukaryotes, especially higher eukaryotes such as mouse and human being. This, they should play a significant role during their host genomes evolution. SINEs occupied 40%-45% of the genomes in mouse and human genomes. This study we do some research as follows:(1) pioneered a package of programs to identify the SINE; (2)identified the SINEs in Bombyx mori, Manduca sexta, Danaus plexippus and Heliconius melpomene at genome level; (3) Through counting the distribution range of SINEs in the genome, we found that SINEs prefer to reside in the non-functional regions; (4) most of SINEs inserted into genome in the recent 3 mya, BM1 and BmSE have experienced a burst amplification.

The distribution of a phenotypic state is often discontinuous and dispersed. As an example of such a distribution, we focused on the shell shapes of terrestrial gastropods, which exhibit a bimodal distribution whereby species possess either a tall shell or a flat shell. Their shell shapes and the distribution were proposed to be related to the mechanics of shell stability on substrates with different inclinations. We estimated the shell stability and geometric constraints by using theoretical morphology (Okamoto model and Raup model) and analyzed the empirical distribution of shell shapes. The following conclusions were derived from the results of these estimations and analysis.
(1) The bimodality of shell shape in terrestrial gastropods was caused by the adaptation to the stability.
(2) There are adjustments in shell morphology to have a good stability from constrained shapes.
(3) Middle-spired gastropods have the ability as the generalist for a wide range of substrates.