The elaborate ornaments and weapons of sexual selection, such as the vast array of horns observed in scarab beetles, are some of the most striking outcomes of evolution. How these novel traits have arisen, develop, and respond to condition is governed by a complex suite of interactions that require coordination between the environment, whole-animal signals, cell–cell signals, and within-cell signals. Endocrine factors, developmental patterning genes, and sex-specific gene expression have been shown to regulate beetle horn size, shape, and location, yet no overarching mechanism of horn shape has been described.

Recent advances in microscopy and computational analyses combined with a functional genetic approach have revealed that patterning genes combined with intricate epithelial folding and movement are responsible for the final shape of a beetle head horn.

性选择的精致装饰品和武器，例如在圣甲虫中观察到的大量角，是进化的一些最引人注目的结果。这些新特征如何出现、发展和对条件作出反应是由一系列复杂的相互作用决定的，这些相互作用需要环境、整个动物信号、细胞间信号和细胞内信号之间的协调。内分泌因素、发育模式基因和性别特异性基因表达已被证明可以调节甲虫角的大小、形状和位置，但尚未描述角形状的总体机制。

显微镜和计算分析与功能遗传方法相结合的最新进展表明，模式基因与复杂的上皮折叠和运动相结合，是甲虫头角最终形状的原因。