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蓝脚鲣鸟，加拉帕戈斯群岛, 厄瓜多尔 (© Karine Aigner/TANDEM Stills + Motion)在求偶时，雄性蓝脚鲣鸟会把那双醒目的蓝色脚掌当作“王牌”，配合夸张的舞步来博得雌鸟青睐。

它先把脚高高抬起，在雌鸟面前昂首阔步地走动，展开一场精心设计的表演。

达尔文日纪念的不只是一位科学家的诞生，更是一场人类思维方式的转变。

查尔斯·达尔文以敏锐的目光观察世界，从个体差异、生存优势到性状遗传，逐步建立起全新的科学认知。

多年研究雀鸟、化石和藤壶后，他逐渐识别出其中隐藏的规律，并在1859年出版《物种起源》，首次系统提出物种通过自然选择不断演化的理论框架。

在达尔文相关的研究中，常被提及的动物之一，正是今天画面里的蓝脚鲣鸟。

这些海鸟广泛分布于加拉帕戈斯群岛及整个东太平洋热带海域，以一双醒目的蓝色脚掌闻名。

脚色的深浅受食物影响——沙丁鱼、凤尾鱼等鱼类中的类胡萝卜素，塑造了它们独特的外观。

无论雌雄，脚掌越鲜亮，往往代表健康状况越好、免疫系统越强。

在求偶时，雄鸟会刻意高举双脚展示，而脚色更浓的雌鸟，也更可能孕育出体质健壮的后代。

捕食时，它们会从高空高速俯冲入海，凭借敏锐的视力精准锁定鱼群。

蓝脚鲣鸟的存在，正是进化仍在继续的生动例证。

Darwin DayDarwin Day marks more than a birthday—it marks a shift in thinking. Charles Darwin's observations connected variation, the survival of individuals best suited to their environment, and inheritance in ways science still builds on. His legacy rests on years of studying variation—finches, fossils, barnacles—and recognizing patterns others had overlooked. When 'On the Origin of Species' was published in 1859, it offered a framework explaining how species evolve through natural selection.One of the most recognizable animals tied to Darwin's work is the blue-footed booby, seen in today's image. Widely associated with the Galápagos Islands, these seabirds range across the eastern tropical Pacific. They are known for their bright blue feet, a trait shaped by both diet and sexual selection. The color comes from carotenoid pigments obtained through fish such as sardines and anchovies. In both male and female, brighter feet signal better health and a stronger immune system. Males display their feet prominently during courtship, while females with more vivid pigmentation tend to produce healthier offspring. These birds hunt by diving straight into the water at high speed, using sharp eyesight to target schooling fish. Boobies stand as a reminder that evolution isn't a closed chapter—it's an ongoing process.点击下方阅读原文，获得更多精彩内容扫码关注每日更新扫码进入微信小程序，每天0点准时更新