Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

NUS Researchers Discover for the First Time That a Rare Bush Frog Breeds in Bamboo

29.10.2014

Scientists observed this new reproductive mode in critically endangered white spotted bush frogs in South India’s Western Ghats

Researchers from the National University of Singapore (NUS) have discovered a new reproductive mode in frogs and toads - breeding and laying direct developing eggs in live bamboo with narrow openings - which was observed in the white spotted bush frog (Raorchestes chalazodes). This critically endangered frog is currently only one of two species known to adopt this novel reproductive strategy. The findings were published in The Linnean Society of London’s Biological Journal of the Linnean Society, in October 2014.


Seshadri K S

Researchers from the National University of Singapore have discovered a new reproductive mode in frogs and toads - breeding and laying direct developing eggs in live bamboo with narrow openings - which was observed in the white spotted bush frog (Raorchestes chalazodes).

Life history strategies to increase reproductive success are termed as reproductive modes. Frogs and toads currently exhibit 40 known reproductive modes, including 17 aquatic modes and 23 terrestrial modes. This study reports the discovery of the 41st reproductive mode which is different from all other known modes – breeding in live bamboo with narrow slits through which adults enter and deposit direct developing eggs and provide parental care. Direct-developing eggs are eggs that hatch as frogs directly.

The species of frogs that exhibit this behaviour, R. chalazodes, was thought to be extinct for over 100 years until it was rediscovered recently in the wet evergreen forests of the Kalakad Mundanthurai Tiger Reserve in the Western Ghats. This biodiversity hotspot of India is listed as a UNESCO World Heritage Site.

In this study, Mr Seshadri K S, a PhD student, and Assistant Professor David Bickford from the Department of Biological Sciences at the NUS Faculty of Science, discovered the reproductive strategy of R. chalazodes. Mr Seshadri observed that adult male frogs enter hollow internodes of the flute bamboo Ochlandra travancorica where they vocalise to attract mates.

They make their way into the bamboo through a small opening, possibly made by insects. Female frogs are attracted to the calls and follow suit, laying about 5 to 8 eggs inside the bamboo. Other females may also choose to mate with the male frog and deposit egg clutches in the bamboo. The male stays in the bamboo to take care of the eggs, which develop directly into froglets.

Although the adult frog is small, under 25 millimetres in length, it enters the bamboo with considerable resistance as the narrow openings are often less than 5 to 10 millimetres long and 3 to 4 millimetres wide. The researchers observed that R. chalazodes only breeds in bamboo that have openings at the base of the internode as those with openings at the top would result in collection of water, possibly flooding the eggs or drowning the froglets.

The adult males actively search for openings in bamboo and possibly defend territories. They leave the bamboo for a few hours in the evening to feed and return to look after the eggs. The researchers made these findings after conducting field observations over a period of six months between 2009 and 2012.

Asst Prof Bickford said, “This is a significant discovery in two ways. First, it reiterates that natural history observations, often ignored, are fundamental for understanding evolutionary ecology. Second, it sets a theoretical foundation to ask several interesting questions about the diversity of reproductive modes and the evolutionary pathways behind such amazing amphibian behaviors.”

The second author of the paper, Dr Gururaja K V from the Centre for Infrastructure, Sustainable Transportation and Urban Planning at the Institute of Science, Bangalore, India, had observed that another species of frogs, known as the Ochlandra reed frog (Raorchestes ochlandrae), breeds in internodes of bamboo. While the geographic ranges of these two species do not overlap and nesting occurs inside different species of bamboo, the reproductive mode is comparable.

R. ochlandrae was previously ascribed to a reproductive mode characterised by direct developing eggs deposited in a nest above ground or in the trees. In this study, the researchers did not observe any nest-making behaviour and thus, the mode was reclassified to be the same as R. chalazodes.

The study is timely as R. chalazodes is currently critically endangered with small populations occurring in fewer than five localities. As this species only breeds in bamboo, unregulated overharvesting of bamboo for paper and pulp may destroy breeding habitats and have a negative impact on the long-term viability of populations. It is critical to conduct more studies on these unique frogs, in particular, those that look into developing frog-friendly harvesting techniques in order to conserve them.

Mr Seshadri, the lead author, said, “Amphibians are among the most threatened creatures on earth and yet, we know very little about them. I was enthralled when we observed this behavior and it opened a whole new world for me. There are several evolutionary questions that could be answered by studying this fascinating group of frogs. For example, what transpires inside the bamboo internodes is still a mystery. The Western Ghats is a well-known hotspot for amphibian diversity which is facing threats primarily from habitat loss. If we do not initiate conservation efforts, we may lose everything before we even document anything.”

Dr Gururaja said, “While species diversity has increased, very little ecological information has been added. The recent discoveries of interesting behaviour such as foot-flagging in the dancing frog (Micrixalus kottigeharensis), and clay nest-building in the potter frog (Nyctibatrachus kumbara) are a case in point that there is much more to be discovered in India and Southeast Asia.”

Contact Information
Kimberley WANG
Assistant Manager, Media Relations
Office of Corporate Relations
National University of Singapore
Email: kimberley.wang@nus.edu.sg

Kimberley WANG | newswise
Further information:
http://www.nus.edu.sg

Further reports about: Bamboo NUS behaviour breeding discovered diversity eggs frogs reproductive

More articles from Ecology, The Environment and Conservation:

nachricht 100 % Organic Farming in Bhutan – a Realistic Target?
15.06.2018 | Humboldt-Universität zu Berlin

nachricht What the size distribution of organisms tells us about the energetic efficiency of a lake
05.06.2018 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

Im Focus: Photoexcited graphene puzzle solved

A boost for graphene-based light detectors

Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...

Im Focus: Water is not the same as water

Water molecules exist in two different forms with almost identical physical properties. For the first time, researchers have succeeded in separating the two forms to show that they can exhibit different chemical reactivities. These results were reported by researchers from the University of Basel and their colleagues in Hamburg in the scientific journal Nature Communications.

From a chemical perspective, water is a molecule in which a single oxygen atom is linked to two hydrogen atoms. It is less well known that water exists in two...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Novel method for investigating pore geometry in rocks

18.06.2018 | Earth Sciences

Diamond watch components

18.06.2018 | Process Engineering

New type of photosynthesis discovered

18.06.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>