TPO32-3 Distributions of Tropical Bee Colonies 热带蜂群的分布

【1】In 1977 ecologists Stephen Hubbell and Leslie Johnson recorded a dramatic example of how social interactions can produce and enforce regular spacing in a population. They studied competition and nest spacing in populations of stingless bees in tropical dry forests in Costa Rica. Though these bees do no sting, rival colonies of some species fight fiercely over potential nesting sites.

Stingless bees are abundant in tropical and subtropical environments, where they gather nectar and pollen from a wide variety of flowers. They generally nest in trees and live in colonies made up of hundreds to thousands of workers. Hubbell and Johnson observed that some species of stingless bees are highly aggressive to members of their species from other colonies, while other species are not. Aggressive species usually forage in groups and feed mainly on flowers that occur in high-density clumps. Nonaggressive species feed singly or in small groups and on more widely distributed flowers.

1977年，生物学家Stephen Hubbell和Leslie Johnson记录下的一个显著例子，表明社会互动能促使其成员形成规律的空间分布。他们研究了Costa Rica热带丛林中无刺蜜蜂的竞争和巢穴分布。它们虽然不蜇人，但其他种类的入侵者却在可能的筑巢地点激烈战斗。

热带和亚热带有大量的无刺蜜蜂，它们从许多种花朵中收集花蜜和花粉。它们通常在树上筑巢，领地内通常有成千上万的工蜂。h和j发现无刺蜜蜂中的某些种类对其他巢穴的同种蜜蜂极具攻击性，而另一些种类却不会。好斗的种类通常集体行动，觅食于高密度生长的花丛。而温和的种类通常单独或小团队觅食，花朵也更广泛地分散。

（1句点明主题，科学家发现社会互动和栖息地分布存在关系。2句，问他们如何得知？答，他们研究了热带干旱雨林中的无刺蜜蜂。 345句回答什么是无刺蜜蜂？有些温和，有些又好斗，分布，习性，栖息地。678句回答，为什么无刺蜜蜂能说明前面说的模式？发现两种蜜蜂的模式不同）

【2】Hubbell and Johnson studied several species of stingless bees to determine whether there is a relationship between aggressiveness and patterns of colony distribution. They predicted that the colonies of aggressive species would show regular distributions, while those of nonaggressive species would show random or closely grouped (clumped) distribution. They concentrated their studies on a thirteen-hectare tract of tropical dry forest that contained numerous nests of nine species of stingless bees.

h和j研究了好几种无刺蜜蜂，意图发现攻击性和居住分布模式之间的联系。他们设想，好斗的蜜蜂将呈现规律的居住分布模式，温和种族则呈现随机或密集分布。他们的研究聚焦在一块热带旱雨林，有九种无刺蜜蜂在这里建立的无数巢穴。

（第二段回答，h和j如何在无刺蜜蜂上研究这一理论？1句他们提出目标，2句他们提出设想。3句他们选定研究区域。）

【3】Though Hubbell and Johnson were interested in how bee behavior might affect colony distributions, they recognized that the availability of potential nest sites for colonies could also affect distributions. So as one of the first steps in their study, they mapped the distributions of trees suitable for nesting. They found that potential nest trees were distributed randomly through the study area. They also found that the number of potential nest sites was much greater than the number of bee colonies. What did these measurements show the researchers? The number of colonies in the study area was not limited by availability of suitable trees, and a clumped or regular distribution of colonies was not due to an underlying clumped or regular distribution of potential nest sites.

尽管h和j的设想是蜜蜂的行为会影响巢穴分布，但他们发现可建巢的地点也会影响分布模式。所以，在研究的第一步，他们将所有能够筑巢的树木都标记出来。他们发现研究区域内这些树木都是随机分布的。而且可供选择的地点远远多于已经建巢的地点。这些测量表明了什么呢？这说明实际分布没有受到可供建巢树木数量的限制，那么，规律或集中的分布模式自然也就没有受限于潜在定居点。

（他们遇到一个问题以及如何解决。1句遇到问题。2345句如何解决。）

【4】Hubbell and Johnson mapped the nests of five of the nine species of stingless bees accurately, and the nests of four of these species were distributed regularly. All four species with regular nest distributions were highly aggressive to bees from other colonies of their own species. The fifth species was not aggressive, and its nests were randomly distributed over the study area.

在九个种类无刺蜜蜂中，h和j精确地画出了五种蜜蜂的巢穴分布，其中四种都呈现规律分布。这四种蜜蜂全都对来自其他定居地的同类具有高度侵略性。第五种并不好斗，他们的巢穴也随机分布在整个研究区域内。

（他们发现了模式。）

【5】The researchers also studied the process by which the aggressive species establish new colonies. Their observations provide insights into the mechanisms that establish and maintain the regular nest distribution of these species. Aggressive species apparently mark prospective nest sites with pheromones, chemical substances secreted by some animals for communication with other members of their species. The pheromone secreted by these stingless bees attracts and aggregates members of their colony to the prospective nest site; however, it also attracts workers from other nests.

研究者还研究了好斗种类蜜蜂建立其巢穴的过程。他们的观察发现了这些蜜蜂建立和保持规律性巢穴分布的机制。显然，好斗种类的蜜蜂会在预期的筑巢地点标记上信息素，这是某些动物为和其成员交流而分泌的化学物质。这些信息素会吸引和聚集它们的居住地的成员，使其来到预期建巢地点；然而，它同样也会引来其他巢穴的工蜂。

（他们进一步研究模式后的原因。）

【6】If workers from two different colonies arrive at the prospective nest at the same time, they may fight for possession. Fights may be escalated into protracted battles. The researchers observed battles over a nest tree that lasted for two weeks. Each dawn, fifteen to thirty workers from two competing colonies arrived at the contested nest site. The workers from the two colonies faced off in two swarms and displayed and fought with each other. In the displays, pairs of bees faced each other, slowly flew vertically to a height of about three meters, and then grappled each other to the ground. When the two bees hit the ground, they separated, faced off, and performed another aerial display. Bees did not appear to be injured in these fights, which were apparently ritualized. The two swarms abandoned the battle at about 8 or 9 a.m. each morning, only to re-form and begin again the next day just after dawn. While this contest over an unoccupied nest site produced no obvious mortality, fights over occupied nests sometimes kill over 1,000 bees in a single battle.

如果来自两个居住点的工蜂同时到达预期地点，它们很可能为占有权战斗。研究者观察到有的巢穴边的战斗可持续两个星期。每次黎明，两边阵营共15-30只工蜂会来到争议巢穴旁。分成两群的工蜂们相遇后会展示然后战斗。在展示部分，两只蜜蜂会面对面，垂直飞到大约3米，然后抓住对方冲向地面。当它们落地，它们会分开，再准备，然后开始又一场空中展示。很显然，蜜蜂在这些斗争中不会受伤，这是仪式化的。两群蜜蜂大约在早上89点会撤离战场，第二天黎明再战。虽然这些发生在未定巢穴边的斗争不会有明显伤亡，为已占巢穴而发动的战争有时会在一场战斗中杀死1000多只蜜蜂。

（描述为预期巢穴的战斗。）

《热带蜂群的分布》的题目下，读者最想知道的问题就是，怎么分布的？为什么？所以，全文先回答分布和社会互动有关。然后通过讲述研究过程一步步证明这个理论的可信。

第一段先说结果，发现模式。第二段开始研究。第三段研究遇到问题并解决。第四段呈现结果。第五段进一步探索背后原因。