<p><b>The Two Subspecies of <i><a href="//commons.wikimedia.org/wiki/Echium_wildpretii" title="Echium wildpretii">Echium wildpretii</a></i>.</b>
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(A) The pink flowers of <i>E. wildpretii trichosiphon</i> are pollinated by insects. (B) The red flowers of <i>E. wildpretii wildpretii</i> are pollinated by generalist native birds, unless birds are driven away by large densities of bees.
Photos courtesy of Alfredo Valido.
CC BY 2.5
Rodríguez-Gironés MA, Santamaría L: <i>Why Are So Many Bird Flowers Red?</i> PLoS Biol 2/10/2005: e350. <a rel="nofollow" class="external free" href="https://dx.doi.org/10.1371/journal.pbio.0020350">https://dx.doi.org/10.1371/journal.pbio.0020350</a>