The following summaries describe recently published research results.
Research 1. Wu and Li (1985): The comparative analysis of homologous genes between human and mouse genomes suggests that the evolutionary rate of homologous genes was higher in the mouse lineage than in the human lineage.
Research 2. Smith and Donohe (2008): The plant families Caprifoliaceae, Asclepiadaceae and Lamiaceae are composed of both herbaceous and arborescent species. The comparative analysis of homologous genes between the herbaceous and arborescent species within a single plant family suggests that the evoluationary rate of homologous genes in herbaceous lineages were faster than that of arborescent lineages in all three plant families.
Research 3. Gilman et al. (2009): The comparative analysis of 130 homologous mitochondrial genes between a sister species pair of vertebrates from the temperate region and from the tropical region indicate that the base substitution rates of homologous genes from the tropical region are 1.7 times faster than that of the temperate region.
Based on these studies, which of the following statements best describes the common evolutionary processes in plant and animal genes?
The following summaries describe recently published research results.
Research 1. Wu and Li (1985): The comparative analysis of homologous genes between human and mouse genomes suggests that the evolutionary rate of homologous genes was higher in the mouse lineage than in the human lineage.
Research 2. Smith and Donohe (2008): The plant families Caprifoliaceae, Asclepiadaceae and Lamiaceae are composed of both herbaceous and arborescent species. The comparative analysis of homologous genes between the herbaceous and arborescent species within a single plant family suggests that the evoluationary rate of homologous genes in herbaceous lineages were faster than that of arborescent lineages in all three plant families.
Research 3. Gilman et al. (2009): The comparative analysis of 130 homologous mitochondrial genes between a sister species pair of vertebrates from the temperate region and from the tropical region indicate that the base substitution rates of homologous genes from the tropical region are 1.7 times faster than that of the temperate region.
Based on these studies, which of the following statements best describes the common evolutionary processes in plant and animal genes?
The correct option is A The evolutionary rates of genes are accelerated in short-lived animals and plants
Short-lived species with quick generation replacement usually evolve at a faster rate than do large, long-lived species. This is because new genetic variations normally appear in each generation as a consequence of mutations in sex cells. Those variations may be selected for or against depending on the environment at the time. As a consequence, quicker reproductive cycles generally result in speeded up species divergence. Speciation is generally a function of time, unlike temperature regions which were subjected to frequent glaciations in the past, tropical latitudes have remained relatively undisturbed for millions of years and thus, have a long evolutionary time for species diversification.So, the correct answer is 'The evolutionary rates of genes are accelerated in short-lived animals and plants'.
Short-lived species with quick generation replacement usually evolve at a faster rate than do large, long-lived species. This is because new genetic variations normally appear in each generation as a consequence of mutations in sex cells. Those variations may be selected for or against depending on the environment at the time. As a consequence, quicker reproductive cycles generally result in speeded up species divergence. Speciation is generally a function of time, unlike temperature regions which were subjected to frequent glaciations in the past, tropical latitudes have remained relatively undisturbed for millions of years and thus, have a long evolutionary time for species diversification.
