英国班戈大学研究团队的最新研究发现，美洲竹节虫在经历超过百万年的孤雌生殖后，其剂量补偿机制仍然保持完整功能，并未出现预期中的退化现象。[1]这一研究成果已发表在《美国国家科学院院刊》上。[1]
该研究由班戈大学进化生物学讲师达伦·帕克博士主导。[1]研究对象为Timema属竹节虫，其孤雌生殖的起源可追溯至约100万至150万年前。[1]Timema属包含约21个物种，主要分布在美国加利福尼亚州至不列颠哥伦比亚省的沿海山脉地区。[1]在超过100万年没有明显选择压力的情况下，这些竹节虫的剂量补偿机制仍然维持着完整的功能。[1]
帕克表示，"这一结果挑战了生物系统在失去选择压力后会迅速退化的传统假设"。[1]
A research team from Bangor University in the United Kingdom has discovered that American stick insects of the genus Timema have maintained fully functional dosage compensation mechanisms despite undergoing parthenogenesis for over a million years, according to findings published in the Proceedings of the National Academy of Sciences (PNAS)[1]. The study, led by Dr. Darren Parker, an evolutionary biologist at Bangor University, challenges the conventional assumption that biological systems rapidly deteriorate when relieved of selective pressure[1].
The Timema genus comprises approximately 21 species distributed across the coastal mountain ranges from California to British Columbia in North America[1]. The shift to asexual reproduction in these stick insects originated between 1 and 1.5 million years ago[1]. Despite this extended period exceeding one million years without apparent selective pressure, the dosage compensation mechanism—a critical biological system—has retained its integrity and function[1]. Parker stated that "this finding challenges the traditional hypothesis that biological systems deteriorate rapidly after losing selective pressure"[1].