Maternal care by Early Cretaceous cockroaches
Maternal care by Early Cretaceous cockroaches
复制标题
早白垩世蟑螂的产妇护理
DOI：
10.1080/14772019.2018.1426059
复制
发表时间：
2019-03-04
影响因子：
2.6
通讯作者：
Ren, Dong
中科院分区：
文献类型：
--
作者：
Gao, Taiping;Shih, Chungkun;Ren, Dong
大多数蟑螂产生一种特殊的囊状结构，即卵鞘，用于包裹卵以保护和照顾母体。然而，由于缺乏中生代的化石证据，蟑螂卵鞘的起源和早期进化知之甚少。本文报道了中国早白垩世义县组中发现的最早的具内裂卵囊的蟑螂化石--该种的卵囊占体长的46-62%，含有60-70个卵，产卵方式为B型，类似于现存的蟑螂和蜚蠊。结合白垩纪中期缅甸琥珀（Burmite）中保存的几个孤立的卵鞘标本，我们推断，使用完整的卵鞘结构的蟑螂生殖模式发生在早白垩世中期或之前。与这些白垩纪蟑螂的卵囊状况相关的母亲护理增加了一个独特而主要的生活史特征，后来导致了真正的胎生。这种新的生活史特征提供了母性保护和照顾，可能是现代蟑螂谱系随后进化多样化和生态扩张的关键因素。
Most cockroaches produce a special capsular structure, the ootheca, to enclose eggs for protection and maternal brood care. However, the origin and early evolution of the cockroach ootheca is poorly known, attributable to a lack of fossil evidence from the Mesozoic. Here, we report the earliest known cockroach fossil possessing an internally partitioned ootheca: Piniblattella yixianensis Gao, Shih & Ren sp. nov. is described from the mid Early Cretaceous Yixian Formation of China. The ootheca of this species measures 46-62% of its body length, contains 60-70 eggs, and exhibits the oviparity B reproduction mode, similar to that of the extant ectobiid and blattid cockroaches. In conjunction with several isolated ootheca specimens preserved in the mid-Cretaceous Myanmar amber (Burmite), we infer that the cockroach reproductive mode using the complete oothecate structure occurred during or before the mid Early Cretaceous. Maternal care associated with the oothecate condition in these Cretaceous cockroaches added a unique and major life-history trait, later resulting in true viviparity. This new life-history trait providing maternal protection and care may have been a key factor in the subsequent evolutionary diversification and ecological expansion of modern cockroach lineages.