Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

African amphibians make extreme parental sacrifice: the skin off their backs

18.04.2006


Just as baby mammals depend on their mothers ’ milk, the young of the African amphibian Boulengerula taitanus nourish themselves by stripping off and eating the fat-rich outer layer of their mothers ’ skin, according to an international team of researchers that includes University of Michigan biologist Ronald Nussbaum.



The findings are reported in today ’s issue (April 13) of the journal Nature.

Hatchlings of B. taitanus—a legless amphibian that looks something like an earthworm—are born with specialized teeth for peeling and eating skin. Their mothers ’ skin is specially modified to be particularly nutritious, and the young depend entirely on this food source for perhaps as long as four weeks, Nussbaum said.


"This form of post-hatching parental care, in which the mother provides nutrition to her hatchlings via her skin, has never been seen before in amphibians, and may be unique among vertebrates to this group of amphibians," said Nussbaum, a professor of ecology and evolutionary biology and a curator in the U-M Museum of Zoology. "Some cichlid fishes are known to provide their hatchlings with nutrition through skin secretions, but this does not include skin feeding."

Earlier observations of another species in the same order of amphibians foreshadowed the latest discovery. In the 1990s, the same research team found that newborn Siphonops annulatus had teeth and stayed with their mothers for some time after hatching. Those observations, coupled with the unusually pale skin color of mothers caring for young, led Nussbaum and colleagues to speculate that S. annulatus hatchlings fed on glandular secretions from the mother ’s skin, but the scientists never observed such behavior.

In the current study, the team collected 21 B. taitanus females along with their broods and put the animals into small, plastic boxes filled with soil to simulate natural nesting conditions. Then they observed and videotaped interactions between young and their mothers.

"We observed eight episodes of skin feeding by different young from five different broods, " Nussbaum said. "In each episode, the young moved over and around their mothers’ bodies, vigorously pressing their heads against their mothers while repeatedly opening and closing their mouths. They used their lower jaws to lift and peel the outer layer of the mother ’s skin. "

Studies of the females ’ skin revealed that the outer layer is up to twice as thick in brooding females as in non-brooding females and is full of nutritious fat.

Amphibians are a diverse lot when it comes to parental care, which may include hiding, guarding, carrying and feeding offspring. Among caecilians—the order of amphibians to which B. taitanus and S. annulatus belong—some lay yolky eggs and tend them until they hatch but invest no energy in feeding the young after hatching; others bear live young that fend for themselves after birth.

In those that bear live young, fetuses are equipped with specialized teeth—something like those of B. taitanus and S. annulatus—that are thought to be used for scraping secretions and cellular material from the lining of the mother ’s oviduct. The skin-feeding behavior seen in B. taitanus may represent an evolutionary intermediate between these two reproductive modes, Nussbaum said.

The discovery of this never-before-seen behavior also highlights the importance of conservation efforts, Nussbaum said. "Concerns have been growing about amphibian populations that appear to be declining worldwide. Our discovery underscores the need for further studies to better document the amazing diversity of amphibian life history strategies and greater efforts to conserve it. "

Nussbaum collaborated on the research with Alexander Kupfer and Mark Wilkinson of the Natural History Museum in London, UK; Hendrik Muller of Leiden University in the Netherlands; Marta Antoniazzi and Carlos Jared of Laboratorio de Biologia Celular, Instituto Butantan in Sao Paulo, Brazil; and Hartmut Greven of the Institut fur Zoomorphologie und Zellbiologie der Heinrich-Heine-Universitat Dusseldorf in Dusseldorf, Germany.

The researchers received funding from the European Union and the Natural Environment Research Council.

Nancy Ross-Flanigan | EurekAlert!
Further information:
http://www.umich.edu

More articles from Ecology, The Environment and Conservation:

nachricht Successful calculation of human and natural influence on cloud formation
04.11.2016 | Goethe-Universität Frankfurt am Main

nachricht Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide

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: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>