The underestimated role of olfaction in avian reproduction?

Abstract

Until the second half of the 20 th century, it was broadly accepted that most birds are microsmatic if not anosmic and unable to detect and use olfactory information. Exceptions were eventually conceded for species like procellariiforms, vultures or kiwis that detect their food at least in part based on olfactory signals. During the past 20-30 years, many publications have appeared indicating that this view is definitely erroneous. We briefly review here anatomical, electrophysiological and behavioral data demonstrating that birds in general possess a functional olfactory system and are able to use olfactory information in a variety of ethological contexts, including reproduction. Recent work also indicates that brain activation induced by sexual interactions with a female is significantly affected by olfactory deprivation in Japanese quail. Brain activation was measured via immunocytochemical detection of the protein product of the immediate early gene c-fos. Changes observed concerned two brain areas that play a key role in the control of male sexual behavior, the medial preoptic nucleus and the bed nucleus of the stria terminalis therefore suggesting a potential role of olfaction in the control of reproduction. The widespread idea that birds are anosmic or microsmatic is thus not supported by the available experimental data and presumably originates in our anthropomorphic view that leads us to think that birds do not smell because they have a rigid beak and nostrils and do not obviously sniff. Experimental analysis of this phenomenon is thus warranted and should lead to a significant change in our understanding of avian biology.

Sequence-based evidence for major histocompatibility complex-disassortative mating in a colonial seabird

“…In mammals and fish, peptides derived from MHC proteins can contribute to individual olfactory profiles that subsequently play a role in mate choice decisions [8,77,78]. Birds appear also to have sophisticated olfactory capabilities [79], and there has been an explosion of studies from a wide range of avian orders showing a link between olfaction and mate choice [80 -82] or other behaviours [83 -85]. Although nothing is known of frigatebird olfaction, female great frigatebirds reject males at both stages of mate choice-at the initial stage of flying over displaying males and also at the subsequent stage of perching in physical contact (Dearborn & Juola 2005, personal observation).…”

Smelling Out Predators is Innate in Birds

“…Nowadays, it has been shown that olfaction may be a more important sense in birds than was traditionally believed (Steiger et al 2008). Recent evidence suggests that birds can use odours in several ecological contexts and with different functions (Roper 1999, Hagelin 2007, Hagelin & Jones 2007, Rajchard 2007, 2008, Balthazart & Taziaux 2009, Caro & Balthazart 2010. At the intra-specific level, they are known to emit chemical compounds, which are important in several aspects of avian life histories (Caro & Balthazart 2010).…”

Red junglefowl have individual body odors

“…Mammals are well known for using olfactory social communication whereas birds are traditionally considered to be microsmatic and to rely on sight and sound rather than olfaction (reviewed by Balthazart and Taziaux, 2009;Hagelin and Jones, 2007;Jones and Roper, 1997). However, a growing body of evidence suggests that olfaction may play an important and hitherto underestimated role for birds in different contexts (Balthazart and Taziaux, 2009).…”

“…However, a growing body of evidence suggests that olfaction may play an important and hitherto underestimated role for birds in different contexts (Balthazart and Taziaux, 2009). A series of studies has shown that seabirds strongly rely on their sense of smell.…”