ECHO · Evolution of the Cochlea and Hearing in Odontocetes
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2017-10-02 → 2019-10-01
- EU contribution
- €195,455
- Participants
- 1
- Scheme
- MSCA-IF-EF-ST
Lines connect the coordinator with its partners.
Results in brief
Evolution of the Cochlea and Hearing in Odontocetes
Knowledge of cetacean hearing has increased in recent years, but still remains biased towards physiological experiments, often on a single species, such as the common bottlenose dolphin. Now, the greatest knowledge gap concerns the acoustic mechanisms of the cochlea, the organ that has the pivotal role of converting sound waves into nerve signals. Studies of cetacean cochlea have not yet progressed beyond qualitative descriptions, which are valuable from a comparative point of view, but add little to our understanding of what frequencies can actually be detected. Hearing abilities are intricately linked to detailed cochlear shape, which can only be determined using quantitative techniques. It is therefore imperative that quantitative shape analyses of the cochlea be undertaken to enable us to truly understand cetacean hearing and its evolution. ECHO has investigated how and when odontocetes evolved their unique sensory abilities, by integrating state-of-the-art 3D imaging, shape quantification and statistical analyses and applying them, for the first time, to the cochlea. The sensitivity of cetacean hearing has rendered them particularly vulnerable to anthropogenic noise pollution, therefore gaining a better understanding of the different sounds these animals are hearing will be important for society and more specifically, inform future conservation and management policies on the effect of this phenomenon. The research objectives of ECHO are as follows: 1. To explore the diversity of the cochlea in living odontocetes. 2. To identify when odontocetes began to use echolocation. 3. To test the extent to which “river dolphins” display convergent evolution in their cochlea.
Data: CORDIS, © European Union
Project objective
Toothed whales (Odontoceti) are a spectacular example of evolutionary adaptation, highly specialised apex predators and a key component of modern ocean ecosystems. The key innovation that has facilitated their evolutionary success is echolocation. Research into odontocete hearing has so far been biased towards physiological experiments and auditory pathway identification; quantitative studies on the cochlea are lacking, despite its critical role in audition. I will fill this gap in knowledge of the cochlea in cetaceans by: (1) quantifying differences in the morphology of odontocete cochlea through the application of cutting-edge scanning, visualisation and quantitative analytical techniques (e.g. 3D geometric morphometrics) to gather in depth data of all features of a fully representative range of odontocete cochlea; (2) testing through statistical analysis whether these differences correlate with, or are driven by, factors such as diet, behaviour or auditory sensitivity; (3) incorporating fossil taxa to pinpoint the timing of the evolution of echolocation; and (4) identifying convergent evolution of specialised high frequency hearing in river dolphins using novel methods for testing and quantifying morphological convergence. This project will create the most comprehensive data set of odontocete inner ear models ever compiled and will mark a major advance in the understanding of cetacean sensory evolution, providing profound insights into how this enigmatic group of marine mammals came to dominate the oceans - making sense of a sixth sense. The data gathered will be made openly available to other researchers.
Original text from CORDIS.
Participants
- NATURAL HISTORY MUSEUM · LondonCoordinatorUnited Kingdom
Links
Data: CORDIS, © European Union