1. A choice or decision made without logical reasoning, facts, or rational thought; a selection based on emotions, impulses, biases, or arbitrary factors rather than objective criteria
His irrational selection of the job offer was based purely on emotion rather than career prospects.
Sua seleção irracional da oferta de emprego foi baseada puramente em emoção em vez de perspectivas de carreira.
2. In evolutionary biology, natural selection that does not follow predictable or logical patterns based on survival advantage
The peacock's elaborate tail feathers result from irrational selection driven by mate preference rather than survival benefit.
As penas elaboradas da cauda do pavão resultam de seleção irracional impulsionada pela preferência de parceiro em vez de benefício de sobrevivência.