Hearing capabilities of bushcrickets and mammals

A new review paper detailing the functional mechanics of katydid (bushcricket) hearing has been published in an international journal.

Dr Fernando Montealegre-Z, from the School of Life Sciences, University of Lincoln, UK, together with Professor Daniel Robert from the University of Bristol, aim to present in detail the functional mechanics of katydid hearing, drawing a parallel between the ear of the bushcricket and tetrapods.

The paper has been published in a special issue of the Journal of Comparative Physiology dedicated to research in insect hearing.

In the animal kingdom many species must identify environmental sounds to increase their chance of survival. Therefore, animals have evolved a vast diversity of mechanisms to detect sounds. Acoustic communication occurs in many groups of animals. Yet, due to their biological diversity, insect species constitute a large percentage of the acoustic community – particularly cicadas, crickets, katydids and grasshoppers. In these groups, males sing to attract females. The Tettigoniidae (or bushcrickets) ear has evolved in the context of intraspecific communication and predator detection.

Dr Montealegre-Z said: “Some insects, like katydids, have evolved biophysical mechanisms for auditory processing that are remarkably equivalent to those of mammals. Located on their front legs, katydid ears are small, yet capable of performing several of the tasks usually associated with mammalian hearing. These tasks include air-to-liquid impedance conversion, signal amplification, and frequency analysis.

“Katydids and tetrapods have evolved remarkably different structural solutions to common biophysical problems. This paper discusses the biophysics of hearing in katydids and the variations observed across different species.”

In 2014 Dr Montealegre-Z was awarded a grant of £250,000 from The Leverhulme Trust to further his study how katydids evolved incredible ultrasonic hearing abilities.

A cochlear organ for frequency selectivity was thought to be unique to hearing in mammals until Dr Montealegre-Z led the team that discovered a similar mechanism for frequency analysis in the ears of bushcrickets in South American rainforests two years ago.

Scientists believe the discovery of this previously unidentified hearing organ could pave the way for technological advancements in bio-inspired acoustic sensors, including medical imaging devices and hearing aids.

The new research project aims to develop an integrated understanding of the evolution of ultrasonic hearing in bushcrickets; specifically how they developed cochlear-like systems in response to changing evolutionary pressures over millions of years.

Fernando Montealegre-Z, Daniel Robert ‘Biomechanics of hearing in katydids’ Journal of Comparative Physiology http://link.springer.com/article/10.1007/s00359-014-0976-1

BBC One documentary features academic’s research

​Research into the hearing abilities of bushcrickets by the School of Life Sciences Dr Fernando Montealegre-Z has been featured by the BBC.

Brought forward from its original transmission date, Super Senses: The Secret Power of Animals was screened by BBC One at 8pm on Tuesday, 26th August.

The series explores the hidden world that animals experience through their senses. The ‘Sound’ episode featured research by Dr Montealegre-Z, who studies how bushcrickets or ‘ katydids’ evolved incredible ultrasonic hearing abilities.

A cochlear organ for frequency selectivity was thought to be unique to hearing in mammals until a similar mechanism for frequency analysis was found in the ears of bushcrickets in South American rainforests two years ago.

Scientists believe the discovery of this previously unidentified hearing organ could pave the way for technological advancements in bio-inspired acoustic sensors, including medical imaging devices and hearing aids.

Dr Montealegre-Z has recently been awarded a £250,000 research grant from The Leverhulme Trust, to further develop an integrated understanding of the evolution of ultrasonic hearing in bushcrickets; specifically how they developed cochlear-like systems in response to changing evolutionary pressures over millions of years.

The episode can be seen here on BBC iPlayer, with the segment on Fernando’s research starting at 50 minutes. It can be viewed until 9th September, 2014.

 

Scientists to explore how insects evolved ultrasonic hearing

A grant of £250,000 from The Leverhulme Trust has been awarded to a team of scientists led by the University of Lincoln, UK, to study how a group of insects evolved incredible ultrasonic hearing abilities.

A cochlear organ for frequency selectivity was thought to be unique to hearing in mammals until a similar mechanism for frequency analysis was found in the ears of bushcrickets in South American rainforests two years ago.

Scientists believe the discovery of this previously unidentified hearing organ could pave the way for technological advancements in bio-inspired acoustic sensors, including medical imaging devices and hearing aids.

The new research project, funded by The Leverhulme Trust, aims to develop an integrated understanding of the evolution of ultrasonic hearing in bushcrickets; specifically how they developed cochlear-like systems in response to changing evolutionary pressures over millions of years.

Project lead Dr Fernando Montealegre-Z, from the School of Life Sciences, University of Lincoln, UK, led the team who discovered the previously unidentified hearing organ in bushcrickets.

He explained: “We will study these hearing systems and their variation in many species of bushcrickets. There are around 7,000 living species of these insects, but what we know about cochlear mechanisms has been investigated in only two or three. Therefore we expect to find enormous amount of variation across species. Through data from fossils and existing species, we aim to unveil major changes in sensory ecological niches and in the auditory ecology of species which have evolved from a single ancestral species.”

Bushcrickets are among the first terrestrial animals to have evolved acoustic communication. The sound emitted by crickets is produced by the stridulatory organ, a large vein running along the bottom of one wing, covered with “teeth”, which is rubbed against a plectrum on the other wing. The ears, located on their forelegs, are used in mating and predator avoidance.

Nearly 70 per cent of the living species, measured with ultrasound-sensitive equipment, produce acoustic signals in the ultrasonic range. However, their ancestors communicated at much lower frequencies. Modern bushcrickets emerged some 55-60 million years ago. Since bats arose at about the same time, the group hypothesise that bushcrickets might have evolved ultrasonic communication and elaborate hearing organs in response to acoustic predators, such as echolocating bats.

For the first time, the group will reconstruct changes in shape and function of fossil bushcrickets’ auditory and stridulatory organs throughout the recorded history of this group, from the Triassic onwards. This will enable them to understand the selective pressures that drove the evolution of cochlear systems in mammals and insects.

The work will enable the construction of a series of biophysical models that will simulate and predict tympanal vibrations and wing resonances in extinct bushcrickets, plus the acoustic reconstruction of the bushcricket community that lived in the long-gone forests of the Triassic and Jurassic eras.

Dr Montealegre-Z said: “Findings will help to comprehend the multiple origins and diversity of auditory mechanisms in mammals and insects. Results will also open up our understanding of the acoustic ecology of extinct environments where other auditory animals lived, and not only provide insights into the lives of singing insects, but that of their prey and predators. Studying fossil insects advances our general understanding of both behavioural and physical ecologies of the forests of the distant past.

“The research encompasses several disciplines including paleontology, biophysics, physiology and engineering. The integration of these disciplines is original and innovative and will open up new opportunities to enhance the current knowledge of sensory mechanisms in living organisms, including humans.”

Samples of fossil material
Samples of fossil material

Research showcased at Royal Society national science exhibition

Two pioneering research projects involving scientists from the School of Life Sciences are featured in a major public exhibition by The Royal Society.

The Royal Society’s prestigious Summer Science Exhibition, which runs from 1st July to 6th July, 2014, is the organisation’s premier public engagement event of the year, showcasing cutting-edge science and technology research in accessible and exciting ways.

Academics will be revealing their ground-breaking work into insect sensory biology and the training of working dogs.

Dr Fernando Montealegre-Zapata from the University of Lincoln and Professor Daniel Robert from the University of Bristol are showcasing their research into the complex hearing mechanisms of insects.

Together with colleagues from Bristol, Dr Montealegre-Z discovered a previously unidentified hearing organ in the South American bushcrickets’ ear. This breakthrough could pave the way for technological advancements in bio-inspired acoustic sensors research, including microphones and cochlear implants.

Their exhibition allows visitors to experience how a Jurassic-era cricket used to sing and a hands-on demonstration will also enable people to hear what a cricket actually hears.

Dr Montealegre-Z said: “This exhibit will allow us to immerse visitors in the world of insect hearing, giving them the opportunity to find out how hearing works at the micro-scale, what exactly it is that insects hear, and how this helps them to find their prey, avoid predators and attract mates.”

Professor Daniel Mills and Helen Zulch, from the School of Life Sciences, and Dr Emile van der Zee from the School of Psychology, are partners in a project with The Open University. Their exhibit focusses on dog-friendly interactive technology used to support or enhance the performance of working dogs which help humans.

Increasingly dogs are humans’ trusted working partners in a wide range of important jobs, such as assisting disabled people, playing crucial roles in military operations, detecting and managing life-threatening medical conditions, or rescuing stranded and injured people.

The Open University Animal-Computer Interaction Lab is currently focussed on designing interactive technologies from a canine perspective. The exhibit showcases prototypes of technologies such as an electronic light-switch designed for assistance dogs; an interface allowing cancer detection dogs to express levels of confidence when assessing biological samples; and an alarm system allowing medical alert dogs to summon help for their assisted humans. Dogs from research partners Dogs for the Disabled and Medical Detection Dogs are also demonstrating the technologies.

Professor Mills said: “This exhibit is a great example of truly interdisciplinary science that has a real impact on society. Dogs were the first species to be domesticated and their partnership with humans is unique. Our work shows how we can use modern technology to help maximise the potential of the partnership and the value that dogs can bring to society.”

 

Technology for Dogs
Technology for Dogs
Helen Zulch at the Technology for Dogs exhibit
Helen Zulch at the Technology for Dogs exhibit
Dr Emile van der Zee at the Technology for Dogs exhibit
Dr Emile van der Zee at the Technology for Dogs exhibit
Dr Emile van der Zee and Helen Zulch
Dr Emile van der Zee and Helen Zulch
3D model of a bushcricket
3D model of a bushcricket
Insect Ear exhibit
Insect Ear exhibit
Insect ear exhibit
Insect ear exhibit

 

Dr Fernando Montealegre-Zapata at the Insect Ear exhibit
Dr Fernando Montealegre-Zapata at the Insect Ear exhibit

Past and present will wow public at air show

Visitors to this year’s RAF Waddington International Air Show can meet a 3D-printed robot and listen to the sound of an insect that lived 165 million years ago.

A new exhibit this year is the ‘Jurassic Acoustic Detective’ , which will explain the story of how the fossil record of a long-extinct insect has been brought to life. Visitors will be able to listen to the sound made by an insect that died 165 million years ago when dinosaurs still stalked the earth and also learn how the extinct Jurassic bushcrickets communicated.

The exhibit is based on the research of Dr Fernando Montealegre-Zapata, Senior Lecturer in the School of Life Sciences, who aims to understand how bushcrickets (or katydids) detect ultrasonic frequencies in their natural environment.

Created by Dr John Murray from the School of Computer Science MARC – Multi-Actuated Robotic Companion – will be meeting the public during the event on 5th and 6th July 2014.

MARC, whose design is supplied by the open source project InMoov, is one of three robots created to help scientists understand how more realistic long-term relationships might be developed between humans and androids.

He will be one of the attractions at the University of Lincoln’s stand which takes on the theme of ‘Robotics and the Natural World’.

The process used to create MARC will be demonstrated with visitors having the chance to 3D-print their own initial.

Dr Murray said: “It’s great to be taking part in the Waddington Air Show once again. People love to see the projects being worked on here at the University of Lincoln and it’s a valuable opportunity to engage with the public and showcase the fantastic research being undertaken by academics from a wide variety of subjects.”

Members of the public can watch an electro-luminescent dance performance given by the University’s Performing Arts students and use the Oculus Rift head-mounted virtual reality headset to experience a CGI ‘fly-through’ of the whole show.

Also on show will be the popular ‘robot football’, which people can control on a purpose-built football pitch, and quadrocopters – the latest sensation in aerial remote control aircraft.

Siren FM, the city’s community radio station based on the University’s Brayford campus, will be at the show all weekend to record the reactions of visitors to the stand.