We amplified the 197 bp HMG box sequence by using Polymerase Chain Reaction (PCR) with primers according to the known SRY sequence from male raccoon genomic DNA, and then cloned and sequenced. The nucleic acid and ami...We amplified the 197 bp HMG box sequence by using Polymerase Chain Reaction (PCR) with primers according to the known SRY sequence from male raccoon genomic DNA, and then cloned and sequenced. The nucleic acid and amino acid sequence comparison between raccoon and other mammals revealed high conservation of the SRY HMG box in mammals (about 80%), which implied that the DNA binding activity was crucial to mediate the action of SRY in sex determination. The variation of raccoon HMG box sequence mainly occurred on purine by replacement and missense mutation, which implicated that only the HMG box protein with advanced structure had efficient activity. The homology and difference between mammals HMG box was accorded to the evolution systematic tree.展开更多
We monitored 15 radio-collared raccoons (Procyon lotor) on Davies Island in March 1987 - May 1988 to determine the extent to which individual tree attributes or spatial configuration of plant associations (habitat typ...We monitored 15 radio-collared raccoons (Procyon lotor) on Davies Island in March 1987 - May 1988 to determine the extent to which individual tree attributes or spatial configuration of plant associations (habitat types) across the landscape influenced den use. Of 1091 verified den sites, 428 were in tree cavities. Raccoon occurrence among 4 cover types differed from that expected based on the total area of each across the island and varied across all seasons for all habitat types except Cedar Wood. Preference varied among age and sex groups and across seasons with some groups showing opposite selection for the same cover type in different seasons. Species and diameter-class distributions of selected den trees differed from a random sample of trees across the landscape. Species composition of trees with cavities also differed from the species composition across the study area. American beech (Fagus grandifolia—relative abundance 8.7%) was over-represented in the sample of trees with cavities (29.4%) and trees selected as dens (65%);diameter at breast height (dbh) of beech den trees averaged 80.0 cm, whereas all beech trees averaged 71.2 cm. For all species combined, mean dbh of den trees was 78.4 cm as compared to trees with cavities (67.6 cm), or all trees (50.4 cm). The relative availability of large, cavity-prone tree species was related to previous logging practices.展开更多
文摘We amplified the 197 bp HMG box sequence by using Polymerase Chain Reaction (PCR) with primers according to the known SRY sequence from male raccoon genomic DNA, and then cloned and sequenced. The nucleic acid and amino acid sequence comparison between raccoon and other mammals revealed high conservation of the SRY HMG box in mammals (about 80%), which implied that the DNA binding activity was crucial to mediate the action of SRY in sex determination. The variation of raccoon HMG box sequence mainly occurred on purine by replacement and missense mutation, which implicated that only the HMG box protein with advanced structure had efficient activity. The homology and difference between mammals HMG box was accorded to the evolution systematic tree.
文摘We monitored 15 radio-collared raccoons (Procyon lotor) on Davies Island in March 1987 - May 1988 to determine the extent to which individual tree attributes or spatial configuration of plant associations (habitat types) across the landscape influenced den use. Of 1091 verified den sites, 428 were in tree cavities. Raccoon occurrence among 4 cover types differed from that expected based on the total area of each across the island and varied across all seasons for all habitat types except Cedar Wood. Preference varied among age and sex groups and across seasons with some groups showing opposite selection for the same cover type in different seasons. Species and diameter-class distributions of selected den trees differed from a random sample of trees across the landscape. Species composition of trees with cavities also differed from the species composition across the study area. American beech (Fagus grandifolia—relative abundance 8.7%) was over-represented in the sample of trees with cavities (29.4%) and trees selected as dens (65%);diameter at breast height (dbh) of beech den trees averaged 80.0 cm, whereas all beech trees averaged 71.2 cm. For all species combined, mean dbh of den trees was 78.4 cm as compared to trees with cavities (67.6 cm), or all trees (50.4 cm). The relative availability of large, cavity-prone tree species was related to previous logging practices.