Data from: Royal Darwinian demons: enforced changes in reproductive efforts do not affect the life expectancy of ant queens

One of the central tenets of life-history theory is that organisms cannot simultaneously maximize all fitness components. This results in the fundamental trade-off between reproduction and lifespan known from numerous animals including humans. Social insects are a well-known exception to this rule: reproductive queens outlive non-reproductive workers. Here, we take a step forward and show that under identical social and environmental condition the fecundity / longevity trade-off is absent also within the queen caste. A change in reproduction did not alter life expectancy, and even a strong enforced increase in reproductive efforts did not result in a reduction of residual lifespan. Generally, egg laying rate and lifespan were positively correlated. Queens of perennial social insects thus seem to maximize at the same time two fitness parameters that are normally negatively correlated. Even though they are not immortal they best approach a hypothetical "Darwinian Demon" in the animal kingdom.生活史理论（life-history theory）的核心信条之一是，生物体无法同时最大化所有适合度组分（fitness components）。由此产生了繁殖与寿命之间的根本性权衡，这一现象在包括人类在内的诸多动物中均有观测记录。社会性昆虫（social insects）则是该规则广为人知的例外：具有繁殖能力的蚁后寿命长于无繁殖能力的工蚁。本研究向前迈进了一步，证实当社会与环境条件完全一致时，蚁后品级（queen caste）内部同样不存在繁殖力-寿命权衡（fecundity/longevity trade-off）。繁殖状态的改变并未影响个体预期寿命（life expectancy），即便强制大幅提升繁殖投入，也未导致剩余寿命（residual lifespan）的缩短。总体而言，产卵速率与寿命呈正相关。因此，多年生社会性昆虫的蚁后似乎同时最大化了通常呈负相关的两项适合度参数。尽管它们并非永生，但已最大限度趋近于动物界中假想的“达尔文恶魔（Darwinian Demon）”。