Mikhaela Neequaye

United Kingdom 6th May 2025 Yellow and Red Mimulus cardinalis Some years ago, scientists examining wild plants in a western corner of the United States encountered a curiously colourful example of biodiversity. Two species of red Mimulus (monkeyflowers) normally pollinated by hummingbirds (Mimulus cardinalis and Mimulus verbenaceus) have unusual, yellow-flowered populations at the edge of their ranges.

Abstract Speciation through the emergence of reproductive isolation barriers is a fundamental concept of evolutionary biology. Here we use two closely related but phenotypically distinct Gymnadenia orchid species and their proposed hybrids to study the barriers associated with this phenomenon. We analysed the potential pre- and post-zygotic barriers to hybridisation and conducted the first comprehensive analysis of pollinator-influenced phenotypic traits in both parents and their hybrids.

Abstract Understanding how evolution proceeds from molecules to organisms to interactions is critical for evolutionary biology and requires integrative studies that span biological levels. By linking phenotypic changes with associated genes and fitness implications, we gain insight on the repeatability of evolution and how adaptive walks move organisms between fitness peaks, which remains poorly understood at intermediate stages, e.g. potential fitness valleys.