Effects of nectar-producing plants (NPP) on the longevity, fecundity, oviposition and nectar-collecting behaviour of Diadegma insulare were studied. Longevity and fecundity of D. insulare were varied with morphological characters of NPP’s flowers. Brassica kaber (D.C) Wheeler, Barbarea vulgaris R. Br. and Daucus carota L. supplied nectar and resulted in D. insulare longevity and fecundity equal...

The African snakehead, Parachanna obscura (Gunther, 1861) is an important food fish in Nigeria and other West countries. To provide useful biological data for management, samples were collected monthly between January, 2011 December, from Ovia River Nigeria. Length-weight relationship (LWR), sex composition fecundity of the species investigated. total lengths ranged 12.8 to 45.7cm, while weight...

We analyzed the trade-offs between fitness components detected in four experiments in which traits were manipulated by inserting small (control) and large (treatment) P-elements into the Drosophila melanogaster genome. Treatment effects and the interactions of treatment with temperature, experiment, and line were caused by the greater length and different positions of the treatment insert. In i...

Since Carlsen and co-workers reported in 1992 that sperm counts have decreased during the second half of the last century in Western societies, there has been widespread anxiety about the adverse effects of environmental pollutants on human fecundity. The Carlsen report was followed by several re-analyses of their data set and by many studies on time trends in sperm quality and on secular trend...

Life-history theory and evolutionary theories of aging assume the existence of alleles with age-specific effects on fitness. While various studies have documented age-related changes in the genetic contribution to variation in fitness components, we know very little about the underlying genetic architecture of such changes. We used a set of recombinant inbred lines to map and characterize the e...

Under the mutation accumulation model of senescence, it was predicted that the additive genetic variance (VA) for fitness traits will increase with age. We measured age-specific mortality and fecundity from 65,134 Drosophila melanogaster and estimated genetic variance components, based on reciprocal crosses of extracted second chromosome lines. Elsewhere we report the results for mortality. Her...

Collar et al. (1994) estimate that of the 9672 extant species of bird, 1111 are threatened by extinction. Here, we test whether these threatened species are simply a random sample of birds, or whether there is something about their biology that predisposes them to extinction. We ask three specific questions. First, is extinction risk randomly distributed among families? Second, which families, ...

The transmission of Plasmodium within a vertebrate host population is strongly associated with the life history traits of its vector. Therefore the effect of malaria infection on mosquito fecundity and longevity has traditionally received a lot of attention. Several species of malaria parasites reduce mosquito fecundity, nevertheless almost all of the studies have focused only on the first gono...

miRNAs and lncRNAs, which represent one of the most highly expressed classes of ncRNAs in development, are attracting increasing interest. A variety of regulators is considered to be implicated in sheep species with different fecundity. However, interactions between miRNAs and lncRNAs and changes in the expression of regulatory lncRNAs in sheep fecundity have not yet been reported. To character...