PDF(Pubmed)
Abstract：
Cooperation is widespread across life, but its existence can be threatened by exploitation. The rise of obligate social cheaters that are incapable of contributing to a necessary cooperative function can lead to the loss of that function. In the social amoeba Dictyostelium discoideum, obligate social cheaters cannot form dead stalk cells and in chimeras instead form living spore cells. This gives them a competitive advantage within chimeras. However, obligate cheaters of this kind have thus far not been found in nature, probably because they are often enough in clonal populations that they need to retain the ability to produce stalks. In this study we discovered an additional cost to obligate cheaters. Even when there are wild-type cells to parasitize, the chimeric fruiting bodies that result have shorter stalks and these are disadvantaged in spore dispersal. The inability of obligate cheaters to form fruiting bodies when they are on their own combined with the lower functionality of fruiting bodies when they are not represent limits on obligate social cheating as a strategy.
摘要：
合作遍布生活，但是它的存在可能受到剥削的威胁。无法为必要的合作功能做出贡献的强制性社会作弊者的兴起可能导致该功能的丧失。在社交阿米巴盘基网柄菌中，专性社交骗子不能形成死茎细胞，而在嵌合体中却形成活孢子细胞。这使它们在嵌合体中具有竞争优势。然而,到目前为止，自然界中还没有发现这种义务作弊者，可能是因为它们通常在克隆种群中足够多，以至于它们需要保留产生茎的能力。在这项研究中，我们发现了义务作弊者的额外成本。即使有野生型细胞寄生，结果的嵌合子实体具有较短的茎，并且在孢子扩散方面处于不利地位。专性作弊者在独立时无法形成子实体，而当子实体的功能较低时，它们并不代表对专性社会作弊作为一种策略的限制。
