This is the first reported study in which various cytological and microbial components of the ear canal of wild jackals (Canis aureus) were examined and compared with those of domesticated dogs (C. domesticus). It is ...This is the first reported study in which various cytological and microbial components of the ear canal of wild jackals (Canis aureus) were examined and compared with those of domesticated dogs (C. domesticus). It is proposed that the differences between them might be attributable to domestication. The normal cytology of the jackals' ears includes cerumen, keratinous debris, coccoid bacteria and yeast-like organisms similar to domesticated dogs, but the frequencies of these findings differed significantly between the two species. In the jackals the incidences of ceruminous debris and yeasts were significantly lower (p p = 0.004 respectively), while keratinous debris and coccoid bacteria were significantly higher (p < 0.001). During domestication some changes have probably occurred in the dogs' lifestyle that predisposed them to the growth of yeasts in their ears but less to bacterial growth. It is possible that the higher numbers of bacteria might be a result of environmental contamination, because some of the jackals lived near urban centers and feed on garbage.展开更多
The present study describes the different color-pattern phenotypes of yellow spots on the black back of Salamandra infraimmaculata in various habitats at the southern border of its distribution in Israel. At Tel Dan, ...The present study describes the different color-pattern phenotypes of yellow spots on the black back of Salamandra infraimmaculata in various habitats at the southern border of its distribution in Israel. At Tel Dan, we photographed 454 salamanders in moist habitats where water flows year round;100 of these were sampled to measure the percentage of yellow and black color on the back, and the number of spots on the head. At Kibbutz Sasa, 201 salamanders were photographed, of which 62 were sampled for the measurements. In Kibbutz Yehiam, 200 salamanders were photographed, and 60 were sampled for the measurements. At all sites, about a third of the salamanders were photographed more than once. For all three populations, yellow spots on the salamander back were found in one row, two rows or scattered. For two indices (proportion of yellow/black and number of spots on the head), the Dan population (under wet, running water all year round conditions) differed from the two other populations of salamanders (under semi-arid mountain conditions). The number of yellow spots on the head of the salamanders in the three populations varied from 1 to 7. In all populations, 4 spots pattern was the most common. In the Dan population, there were significantly more salamanders with 1 to 3 spots on their head than in the Sasa or Yehiam populations. No difference was found in the number of head spots for Sasa vs. Yehiam salamanders. The percentage of yellow on the black back was significantly larger for the Dan salamanders vs. the two other populations. The main question examined was whether there is an effect of the habitat conditions in isolated populations on the spot pattern on the salamander back. The answer is positive and is supported by previous studies.展开更多
文摘This is the first reported study in which various cytological and microbial components of the ear canal of wild jackals (Canis aureus) were examined and compared with those of domesticated dogs (C. domesticus). It is proposed that the differences between them might be attributable to domestication. The normal cytology of the jackals' ears includes cerumen, keratinous debris, coccoid bacteria and yeast-like organisms similar to domesticated dogs, but the frequencies of these findings differed significantly between the two species. In the jackals the incidences of ceruminous debris and yeasts were significantly lower (p p = 0.004 respectively), while keratinous debris and coccoid bacteria were significantly higher (p < 0.001). During domestication some changes have probably occurred in the dogs' lifestyle that predisposed them to the growth of yeasts in their ears but less to bacterial growth. It is possible that the higher numbers of bacteria might be a result of environmental contamination, because some of the jackals lived near urban centers and feed on garbage.
文摘The present study describes the different color-pattern phenotypes of yellow spots on the black back of Salamandra infraimmaculata in various habitats at the southern border of its distribution in Israel. At Tel Dan, we photographed 454 salamanders in moist habitats where water flows year round;100 of these were sampled to measure the percentage of yellow and black color on the back, and the number of spots on the head. At Kibbutz Sasa, 201 salamanders were photographed, of which 62 were sampled for the measurements. In Kibbutz Yehiam, 200 salamanders were photographed, and 60 were sampled for the measurements. At all sites, about a third of the salamanders were photographed more than once. For all three populations, yellow spots on the salamander back were found in one row, two rows or scattered. For two indices (proportion of yellow/black and number of spots on the head), the Dan population (under wet, running water all year round conditions) differed from the two other populations of salamanders (under semi-arid mountain conditions). The number of yellow spots on the head of the salamanders in the three populations varied from 1 to 7. In all populations, 4 spots pattern was the most common. In the Dan population, there were significantly more salamanders with 1 to 3 spots on their head than in the Sasa or Yehiam populations. No difference was found in the number of head spots for Sasa vs. Yehiam salamanders. The percentage of yellow on the black back was significantly larger for the Dan salamanders vs. the two other populations. The main question examined was whether there is an effect of the habitat conditions in isolated populations on the spot pattern on the salamander back. The answer is positive and is supported by previous studies.
