Vines Evolved Before Arrival: A New Evolutionary Twist

Plant biologists have uncovered surprising evidence about lipstick vines, specifically a species with green flowers found in Taiwan. Unlike what was expected, these plants evolved shorter, wider flowers before they spread to Taiwan, a finding that challenges the long-standing Grant-Stebbins evolutionary model. This model typically describes how pollinators drive the formation of new species.

The research indicated that while mainland Asia has sunbirds capable of pollinating long, red flowers, the green-flowered lipstick vines (Aeschynanthus acuminatus) evolved in isolation. Their shorter, wider flowers in Taiwan were pollinated by birds with shorter beaks, adapting to local wildlife. This evolution occurring prior to migration suggests alternative explanations for species diversification.

Further fieldwork also yielded an unexpected discovery in Vietnam, where researchers observed rodents pollinating the lipstick vines. This marks the first documented instance of rodent pollination within this plant genus, highlighting the complex ecological interactions surrounding these plants. The study continues to explore these intricate relationships.