A. Some species are more important than others. B. All species are equally important for maintaining the balance. C. Larger species are the most important. D. Smaller species are less important. 相关知识点: 试题来源: 解析 B。本题考查对生态平衡中不同物种重要性的理解。选项 A“more important...
An acre of tropical forest may include over 100 species of trees, all of which depend on the same soil, water, and nutrients. Freshwater lakes may have dozens of species of fish, all of which feed on the planktonic algae and animals suspended in the water. Indeed, two or more species ...
We are extremely fragile because our existence depends more on other species than they depend on us. 不过对于人类而言,情况就不同了。人类从大灭绝中生存下来的希望很低。人类居于食物链的最顶层,消耗大量食物和资源。我们更多地依赖其它物种,所以非常脆弱。 Actually, a browse of the past five mass extinc...
The extent of interspecific gene flow and its consequences for the initiation, maintenance, and breakdown of species barriers in natural systems remain poorly understood. Interspecific gene flow by hybridization may weaken adaptive divergence, but can be overcome by selection against hybrids, which may ...
environments. This finding echoes earlier studies which suggested that non-native plants may depend more on human disturbance for successful establishment than do non-native tetrapods13. Whether these patterns hold true beyond these regions and taxa remains largely unknown....
rare species may, on average, (1) decline proportionally, (2) decline less or (3) decline more. Each of these scenarios gives distinctive signatures in various biodiversity metrics and in the shape of the SAD (see Fig.1and Box1). There are other possible scenarios consistent with total abu...
These factors may reinforce or contradict trends associated with the flock vigilance hypothesis, in ways that may depend on the sex of the subject and its companions. 6. Temperature and date both influence looking-up and the peck rate. In studies of this type it is clearly important to ...
Clonal plants can successfully adapt to various ecosystems. A trade-off between sexual and clonal reproduction is generally assumed in clonal plants, which may be influenced both by the characteristics of the plant itself and environmental conditions. Cu
3D) may be explained by the fact that both mycorrhizal types could be found in angiosperms or gymnosperms, and that SRL values of angiosperms overlap with gymnosperms values61. The influence of some plant functional types on SOC stability supports the idea that species with nutrient-rich litters...
A pair may reuse the same nest for many years, adding new material each breeding season. Females typically lay one egg, which she incubates while the male provides food. The chick fledges after about 100 days but may depend on its parents for several more months. Unfortunately, Martial ...