Hello everybody,
There is a new scientific article which confirms the supposition that hummingbirds find their flowers mainly by sight, not by scent. Unfortunately, the article is not available for free, but here is the abstract:
Trends in floral scent chemistry in pollination syndromes: floral scent composition in hummingbird-pollinated taxa
JETTE T. KNUDSEN, LARS TOLLSTEN, INGA GROTH, GUNNAR BERGSTRÖM, ROBERT A. RAGUSO
Abstract
We studied an assemblage of 17 species of bird-pollinated Ecuadorian plants (from 14 angiosperm families), including taxa pollinated by short-billed (trochiline) and sickle-billed (hermit) hummingbirds. Hummingbirds are widely supposed to ignore fragrance while visiting flowers. We collected floral headspace odours in order to test the general prediction that specialist hummingbird-pollinated flowers are scentless. In nine out of 17 of these species we failed to detect any odours using gas chromatography-mass spectrometry (GC-MS), whereas the remaining eight species produced trace levels of volatile compounds. Most of these odour compounds were of terpenoid or lipoxygenase derivation and are commonly emitted by vegetative as well as floral plant tissues. Further studies will be required to determine whether these weak odours attract alternative pollinators, repel enemies or represent vestiges of a scented ancestry. © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society, 2004, 146, 191–199.
There is a new scientific article which confirms the supposition that hummingbirds find their flowers mainly by sight, not by scent. Unfortunately, the article is not available for free, but here is the abstract:
Trends in floral scent chemistry in pollination syndromes: floral scent composition in hummingbird-pollinated taxa
JETTE T. KNUDSEN, LARS TOLLSTEN, INGA GROTH, GUNNAR BERGSTRÖM, ROBERT A. RAGUSO
Abstract
We studied an assemblage of 17 species of bird-pollinated Ecuadorian plants (from 14 angiosperm families), including taxa pollinated by short-billed (trochiline) and sickle-billed (hermit) hummingbirds. Hummingbirds are widely supposed to ignore fragrance while visiting flowers. We collected floral headspace odours in order to test the general prediction that specialist hummingbird-pollinated flowers are scentless. In nine out of 17 of these species we failed to detect any odours using gas chromatography-mass spectrometry (GC-MS), whereas the remaining eight species produced trace levels of volatile compounds. Most of these odour compounds were of terpenoid or lipoxygenase derivation and are commonly emitted by vegetative as well as floral plant tissues. Further studies will be required to determine whether these weak odours attract alternative pollinators, repel enemies or represent vestiges of a scented ancestry. © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society, 2004, 146, 191–199.