权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Fish Communities in Lake Tanganyika, Their Ecology and Evolution

坦噶尼喀湖鱼类群落及其生态和进化

基本信息

批准号：
63041080
负责人：
KAWANABE Hiroya
金额：
$ 16.58万
依托单位：
Kyoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for international Scientific Research
财政年份：
1988
资助国家：
日本
起止时间：
1988 至 1990
项目状态：
已结题

项目摘要

Our field studies in the last decade have documented that cooperative interspecific relationships as well as competitive ones are highly incorporated in coastal fish communities in Lake Tanganyika. The great diversity of the fish community is attributed to the explosive adaptation of cichlids in this lake. Our phylogenetic study of this fish group by allozyme electrophoresis indicated that at least seven old, ancestral lineages contributed to present cichlid fauna and this lake can be recognized as an evolutionary reservoir of major lineages of cichlids in East Africa.The species composition varies geographically within that lake. Fish fauna of the southern region was investigated for the first time at Mupulungu, Zambia in 1988 and 1989 and compared with that of the central (Mahale, Tanzania) and northern (Luhanga and Pemba, Zaire) regions surveyed before. The species number was greater in the southern region by 10 species than in the central and northern regions and a quarter of the s … More pecies were endemic to the southern region. Some equivalent niches were occupied by related but different species among the three regions. In a group of cichlids using shells for spawning, most of which are endemic to the southern region, a host-parasite relationship was recognized during their reproduction.Polymorphism in body color and jaw laterality within a population was found in some piscivorous or lepidophagous species. This polymorphism was closely linked to hunting tactics. The foraging efficiency of each morph can increase because of the difficulty of defense for a prey against predators each having specialized hunting tactics. This intraspecific "cooperation" and the interspecific cooperation between species in the same guild, found in our previous study, indicate that interdependent relationships are important elements on various levels of the community organization.The flexibility in the habitat utilization among cohabiting related species was also studied. When several species of algal eaters were removed from an area, the same species re-occupied the same sites. Similarly, in successive removal experiments of brooding pairs in 12 lamprologini species for one year, the same breeding sites were re-occupied by the same species. These results suggest that for the use of microhabitat each species has a narrowly tuned adaptive zone and microhabitats are usually not exchangeable between species. Less

我们过去十年的实地研究表明，坦噶尼喀湖沿岸鱼类群落中高度融合了种间合作关系和竞争关系。鱼类群落的巨大多样性归因于该湖慈鲷的爆炸性适应。我们通过同种酶电泳对这个鱼群进行的系统发育研究表明，至少有七个古老的祖先谱系促成了现在的慈鲷动物群，这个湖可以被认为是东非慈鲷主要谱系的进化库。该湖内的物种组成因地理位置而异。 1988年和1989年首次在赞比亚穆普隆古对南部地区的鱼类区系进行了调查，并与之前调查的中部地区（坦桑尼亚马哈勒）和北部地区（扎伊尔卢安加和彭巴）进行了比较。南部地区的物种数量比中部和北部地区多10种，其中四分之一的物种是南部地区特有的。三个区域中一些相同的生态位被相关但不同的物种占据。在一群以贝壳产卵的丽鱼科动物中，大多数是南方地区特有的，在它们的繁殖过程中发现了宿主与寄生虫的关系。在一些鱼食性或鳞食性物种中发现了种群内体色和下颌偏侧性的多态性。这种多态性与狩猎策略密切相关。由于猎物很难防御具有专门狩猎策略的掠食者，因此每种变体的觅食效率都会提高。我们之前的研究发现，这种种内“合作”以及同一行会中物种之间的种间合作，表明相互依存关系是群落组织各个层面的重要组成部分。同时还研究了同居相关物种之间栖息地利用的灵活性。当几种食藻类动物从一个地区被清除时，相同的物种会重新占据相同的地点。同样，在连续一年对 12 个蜥蜴物种的育雏对进行去除实验中，相同的繁殖地点被相同的物种重新占据。这些结果表明，对于微生境的使用，每个物种都有一个狭窄的适应区，并且微生境通常在物种之间不可交换。较少的