The influence of species frequency, temperature regime and previous development condition on relative competitive ability between Drosophila melanogaster and Drosophila simulans

Abstract

Some fitness components of Drosophila melanogaster and D. simulans were measured in control and interspecific competition tests. The effects derived from different relative frequencies of the competitors were examined under a factorial scheme with two temperatures, 21 °C or room temperature, and with adults developed in mixed-or pure-species cultures. D. melanogaster appeared as a strong competitor and outnumbered D. simulans in all the culture conditions. This was because intraspecific competition was stronger than interspecific competition for D. melanogaster whereas the reverse occurred for D. simulans. In competition, the productivity of both species generally appeared as frequency-dependent, although density-dependent productivity seems to be a more accurate explanation.D. simulans was very sensitive to variations of laboratory conditions. Room temperature and previous development with D. melanogaster were more favorable for D. simulans than 21 °C and previous development in pure cultures. These factors did not substantially affect D. melanogaster, which showed a greater ability of adaptation to laboratory conditions than its sibling D. simulans.

Identifying factors determining the altitudinal distribution of the invasive pest leafminersLiriomyza huidobrensisandLiriomyza sativae

“…However, direct effects of environmental factors might not always explain distribution patterns of insects (Lomolino, 2001;Eyre et al, 2005) and in these cases altitudinal effects on species interactions might be involved. The altitudinal distribution of species might be influenced by changes in competitive ability with environmental conditions (Carracedo & Casares, 1986), or the effects of altitude on natural enemies that attack different host species (Randall, 1982;Preszler & Boecklen, 1996). Altitude can also influence species abundance by affecting the quality and distribution of host plants, as in the case of tephritid flies and leaf mining moths (Preszler & Boecklen, 1996;Yarnes & Boecklen, 2006;Kubota et al, 2007).…”

The neurodevelopmental genesalan shepardandNeurogliancontribute to female mate preference in AfricanDrosophila melanogaster

“…One example in Drosophila suggests that the genetic architecture of premating isolation can be variable. When different strains of D. simulans were crossed and tested for mate rejection of D. melanogaster, different numbers, locations, and dominance of quantitative trait loci were identified that were strain specific (Uenoyama and Inoue, 1995; Carracedo et al, 1998a; Carracedo et al, 1998b; Carracedo et al, 2000). The variation in dominance and the number of loci contributing to mate preference in D. simulans might be consistent with this barrier evolving after the speciation event that separated these lineages (Laturney and Moehring, 2012).…”

Does Temperature-Mediated Reproductive Success Drive the Direction of Species Displacement in Two Invasive Species of Leafminer Fly?

“…Our results provide evidence that significant differences in interspecific interactions can occur within a relatively narrow temperature range. Slight differences in temperature are known to alter the outcome of competitive interactions of species with similar life histories to Liriomyza spp [25] , [41] . Other factors, such as differential effects of natural enemies, host plants or insecticides also are likely to influence the populations of these pests, but it is clear that temperature can be a significant factor in altering competitive interactions between these species.…”