动物对孢子植物的传播模式及进化意义

Dispersal of spore plants by animals:Patterns and evolutionary significance

孢子植物物种多样性丰富,是自然生态系统的重要组成部分。孢子植物的传播通常被认为主要依靠风、水、弹力等非生物媒介,而动物的作用往往被忽略。本文主要概述了:(1)孢子植物对动物传播的适应:一方面孢子植物可为动物提供食物、庇护所、繁殖场所等,另一方面孢子植物也可产生视觉、嗅觉等方面的线索来吸引动物,从而促进动物传播其繁殖体。(2)动物对孢子植物的传播模式:包括体内传播(消化道和组织寄生)和体外传播两种,这些模式都能对孢子植物繁殖体进行有效传播。由于动物间形态或生活习性的不同,以致传播距离存在差异,最短距离为0.1 cm,最长距离可从北半球至南半球。(3)动物对孢子植物传播的生态与进化意义;由于某些孢子植物繁殖体的结构特点或萌发的需求,以致其繁殖体只能通过动物的传播才能得以定殖,因此动物与孢子植物之间存在密不可分的关系。目前,动物对孢子植物的传播研究主要是描述性的内容以及研究单方面的传播途径,建议在今后的研究中考虑动物对孢子植物传播的有效性以及多途径同时传播对孢子植物定殖的影响,同时应更加关注孢子植物和动物互惠关系的形成、维持机制及将来的进化趋势。

Background&Aims:Spore plants,as an important food source for terrestrial animal,play a vital role in maintaining the subtle balance of the earth’s ecological system.Animals and spore plants may also together form an interaction system similar to the network of zoochorous seed dispersal.Therefore,the effect of animals on spore plant propagules dispersal has been receiving increasing attention.Here,we summarize that(1)the adaptation of spore plants to dispersal by animals.On the one hand,spore plants can provide food,shelters and breeding sites for animals;on the other hand,spore plants can also produce visual and/or olfactory cues and so on to attract animals in order to increase their propagule dispersal.(2)the two zoochorous dispersal patterns of spore plants that can effectively disperse propagules of spore plants,namely endozoochory(through the digestive tract and parasitism)and epizoochory.Due to the different morphological characteristics and life habits between animals,the distance of dispersal is also different,with the shortest distance of 0.1 cm and the longest distance from the northern hemisphere to the southern hemisphere.(3)The ecological and evolutionary meanings of zoochorous dispersal of spore plants.For some spore plant propagules,due to their special structural characteristics or particular need for germination,the propagules can only be dispersed by specific animals,which leads to an inseparable relationship between such animals and spore plants.At present,few studies in this field have been conducted in China.The researches on spore plant dispersal in other countries are mainly descriptive,most of which are independent pattern on spore plant dispersal.Prospects:We propose that more consideration should be given to the multi-pattern dispersal and mutualistic relationship between animals and spore plants in future studies,as well as the formation,maintenance mechanism and future evolutionary trends of spore plant-animal relationships.