Trilobites might have nose-jousted

Male trilobites of the species Walliserops trifurcatus might have used their huge trident-shaped horn in jousting matches to win females’ favour 400 million years ago. The idea is reminiscent of the modern Japanese rhinoceros beetle (Trypoxylus dichotomus), which flips opponents with its rake-like horn. The trilobite’s horn isn’t mobile enough to be an effective defence and is too long and oddly angled for foraging. And scientists have found a fossil of an adult trilobite with a deformed trident, suggesting that the structure wasn’t crucial for survival. This might be the oldest example of specialised sexual combat.