摘要
从动物 -植物协同进化模式、植物对动物采食反应及动物对植物防卫的适应对策等方面综述了以植物次生化合物为媒介的植食性哺乳动物 -植物协同进化的研究进展。动物与植物的协同进化模式包括成对协同进化、扩散协同进化、躲避-辐射协同进化、多样性的协同进化、平行分枝进化、互惠进化等模式。植物不仅以超补偿反应 ,物理防卫作为对植食性动物采食的应答 ,延长植食性动物的觅食时间 ,降低植食性动物的觅食效率 ,更能以其派生的次生化合物抑制动物的摄食 ,进而影响其消化、代谢及生长等生理生态特征。动物通过改变觅食行为 ,调整对各食物项目的相对摄入量 ,减少次生化合物的摄入量 ;动物还通过氧化、还原、络合、改变消化道内环境、形成相应的降解酶、改变代谢率等途径降低次生化合物对其的负作用。
The proceeding of coevolution of mammalian herbivores and plant mediated by plant secondary compounds was reviewed, based on the modes of coevoluiton of animal \|plant. Coevolution is viewed as “evolution of a trait of one species in response to a trait of another species, which trait itself has evolved in response to a trait in the first species”. The modes of coevolution of animal\|plant includes pairwise coevolution, diffuse coevolution, escape\|radical coevolution, diversifying coevolution, parallel cladogensis (cospeciation), reciprocal evolution et al. Pairewise coevolution requires that the participants exhibit evolutionary interactions over long periods of time. Diffuse coevolution and herbivore adaptation to plant metabolites may occur over long or relatively short periods depending on the intensity of interaction. Coevolution may or may not involve cospeciation. Possibly the only consistent aspect of definitions for evolution is the requirement for some form of reciprocity of evolutionary change. Many plants increase their growth and canopy photosynthetic to overcompensation the grazing of herbivores. The density of prickle, thorns and production of secondary compounds in plants can be increased by the browsing of mammalian herbivores. Herbivores must carefully manipulate the plant in their mouths to avoid the thorns and spines. This may reduces the rate at which the plant can be harvested in two ways. First, to avoid spines, herbivores must spend more time plucking and chewing plant. Second, the thorns and spines force the herbivores to pluck smaller items from the plant, which reduces the amount of food the herbivore ingests per unit time. Plant chemical defense is one of ways that plants avoid from mammalian herbivory. Such chemical defense involves the elaboration and accumulation of organic substances. The substances may be bitter\|tasting, poisonous, offensive odor. Plant secondary compounds affect digestibility, metabolism or toxic to mammalian herbivores, and reducing the preference for herbivores. If plant poisons are defense mechanisms, it would be logical to assume that coevolution has occurred in herbivores to prevent their being poisoned by plants. Some of possible evolutionary strategies in herbivores used to deal with plant secondary compounds are made up two parts: the animal's behavior and its physiological capability. Herbivores may avoid plants containing chemical defenses; limited consumption of secondary chemicals, or select the plants containing particular chemicals. Feeding behavior of mammalian herbivores depends on the individual mammal's capability of detoxifying and /or tolerating the biological effects of particular individual or combinations of plant secondary compounds. There are at least six physiological mechanisms for diminishing the activity of plant secondary compounds: (1) formation of a less reactive complex, (2) modification of the environment to inhibit reactions, (3) degradation, (4) addition of functional groups, (5) conjugation to change solubility, (6) alteraction of metabolic rate. Energy of mammalian herbivores evolve as a last line of defense against the extensive array of toxic substances that exist in the environment in the form of secondary compounds and venoms.
出处
《生态学报》
CAS
CSCD
北大核心
2002年第12期2186-2193,共8页
Acta Ecologica Sinica
基金
国家自然科学基金资助项目 (3 9970 1 3 3 )
中国科学院海北高寒草甸生态系统定位站资助项目
