Department of Biology, New Mexico State University, Las Cruces, NM 88003-8001, USA.
J Chem Ecol. 2011 Jan;37(1):10-7. doi: 10.1007/s10886-010-9901-4. Epub 2010 Dec 17.
Many organisms provision offspring with antipredator chemicals. Adult blue-ringed octopuses (Hapalochlaena spp.) harbor tetrodotoxin (TTX), which may be produced by symbiotic bacteria. Regardless of the ultimate source, we find that females invest TTX into offspring and offspring TTX levels are significantly correlated with female TTX levels. Because diversion of TTX to offspring begins during the earliest stages of egg formation, when females are still actively foraging and looking for mates, females may face an evolutionary tradeoff between provisioning larger stores of TTX in eggs and retaining that TTX for their own defense and offense (venom). Given that total TTX levels appear to increase during development and that female TTX levels correlate with those of offspring, investment may be an active adaptive process. Even after eggs have been laid, TTX levels continue to increase, suggesting that offspring or their symbionts begin producing TTX independently. The maternal investment of TTX in offspring of Hapalochlaena spp. represents a rare examination of chemical defenses, excepting ink, in cephalopods.
许多生物为其后代提供抗捕食者的化学物质。成年蓝环章鱼（Hapalochlaena spp.）体内含有河豚毒素（TTX），这种毒素可能由共生细菌产生。无论最终来源如何，我们发现雌性会将 TTX 注入后代体内，而且后代体内的 TTX 水平与雌性体内的 TTX 水平呈显著正相关。由于 TTX 向后代的转移始于卵子形成的最早阶段，此时雌性仍在积极觅食并寻找配偶，因此雌性可能在为卵子提供更多 TTX 储备和保留 TTX 用于自身防御和进攻（毒液）之间面临着进化上的权衡。鉴于总 TTX 水平似乎在发育过程中增加，并且雌性 TTX 水平与后代的 TTX 水平相关，因此投资可能是一个积极的适应性过程。即使卵子已经产下，TTX 水平仍在继续增加，这表明后代或其共生体开始独立产生 TTX。Hapalochlaena spp. 的后代从母体获得 TTX，这代表了对除墨汁以外的头足类动物化学防御的罕见研究。
