Causes and consequences of signal divergence across species

I am broadly interested in why signals differ across species and the consequences of this variation for important evolutionary processes, such as the evolution of reproductive isolation, cooperation, and sensory biases. I am currently a postdoctoral researcher at Uppsala University working with Anna Qvarnström, Animal Ecology, and a visiting researcher with Finn Hallböök, Neuroscience. In 2012, I completed my PhD in Trevor Price's lab at the University of Chicago and, from 2012-2014, completed a NSF research fellowship with Anna Qvarnström in Uppsala. I've been lucky enough to work in variety of songbird systems to explore:

What factors lead to signal divergence across species?

How do individuals come to recognize the (variable) signals of other species?

What mechanisms focus learning onto relevant signals?


Contact

davidjameswheatcroft "at" gmail "dot" com

david "dot" wheatcroft "at" ebc"dot" uu "dot" se




1)
Associative learning and the evolution of alarm calls


Awareness of the alarm calls of surrounding species can prove greatly beneficial to individuals living in multi-species communities, because they can acquire critical information about predators from multiple sources.

Calls generally vary greatly across even closely related species. Despite dissimilarity across species, a combination of learning and recognition of common acoustic features allows widespread communication. In extreme cases, communication between a pair of species may even promote call convergence through copying or mimicry.

My work also addressed why alarm calls vary across species. We demonstrated that the number and variety of receivers may strongly influence the rate and nature of signal divergence: alarm calls directed at a narrower set of receivers evolve at slower rates than those directed at a more diverse set of receivers.

Relevant papers

1) Wheatcroft D & Price TD (2013) Learning and signal copying facilitate communication among bird species.
Proceedings of the Royal Society B 280, 20123070 link


2) Wheatcroft D & Price TD (2014) Rates of signal evolution are associated with the nature of interspecific communication. Behavioral Ecology, aru161 link


3) Wheatcroft D (2015) Repetition rate of calls used in multiple contexts communicates presence of predators to nestlings and adult birds. Animal Behaviour 103, 35-44 link


4) Wheatcroft D, Gallego-Abenza M, & Qvarnström A (2016) Species replacement reduces community participation in avian antipredator groups. Behavioral Ecology link

2) The role of innate auditory perception in song learning and speciation

I use playback experiments, acoustic analysis, and neurobiological methods to study the genetic and neural basis of auditory perception in two species of closely related, co-occurring songbirds, the pied (Ficedula hypoleuca) and collared flycatcher (F. albicollis).

Relevant papers

1) Wheatcroft D & Qvarnström A (2015) A blueprint for vocal learning: auditory predispositions from brains to genomes. Biology Letters 11, 20150155 link


2) Wheatcroft D (2015) Reproductive interference via display signals: the challenge of multiple receivers. Population Ecology 57, 333-337 link


3) McFarlane SE, Söderberg A, Wheatcroft D, & Qvarnström A (2016) Song discrimination by nestling collared flycatchers during early development. Biology Letters 12, 20160234 link

More to come soon...