The odd lifestyle of the Pacific leaping blenny (Alticus arnoldorum) has been detailed for the first time in research findings that throw new light on how animal life first evolved to colonise the land.
The Pacific leaping blenny is a marine fish yet is terrestrial in all aspects of its daily adult life, eking out a precarious existence in the intertidal zone of rocky shores in Micronesia, according to the study published in the journal Ethology , led by Dr Terry Ord, of the UNSW Evolution and Ecology Research Centre.
"This remarkable little fish seems to have made a highly successful transition across the water–land interface, although it is still needs to stay moist to enable it to breathe through its gills and skin," says Dr Ord, who is an evolutionary ecologist with a special interest in animal behaviour.
"Our study showed that life on land for a marine fish is heavily dependent on tide and temperature fluctuations, so much so that almost all activity is restricted to a brief period at mid-tide, the timing of which changes daily. During our field study on Guam we never saw one voluntary return to water. Indeed, they spend much of their time actively avoiding submersion by incoming waves, even when we tried to capture them for study.
"I can tell you they are very hard to catch and are extremely agile on land. They move quickly over complex rocky surfaces using a unique tail-twisting behaviour combined with expanded pectoral and tail fins that let them cling to almost any firm surface. To reach higher ground in a hurry, they can also twist their bodies and flick their tails to leap many times their own body length."
Working with Toni Hsieh, of Temple University in the US, Dr Ord found that adult blennies shelter in rock crevices at high and low tide, emerging at mid-tide to feed, breed and socialise in surprisingly complex ways – given their brief window of opportunity.
The researchers discovered that males are territorial and use complex visual displays to warn off rivals and attract mates. Females were seen aggressively defending feeding territory at the start of their breeding season, while males displayed a red-coloured fin and nodded their heads vigorously to attract females to their closely defended rock holes. The team filmed females inspecting these holes before entering with a chosen mate.
Little is known of their breeding and development of the young, but it seems that females lay their eggs in a chosen rock hole then play no further role in parenting, leaving the male to guard the eggs.
"The Pacific leaping blenny offers a unique opportunity to discover in a living animal how a water–land transition has taken place," says Dr Ord.
"We know that our ancient ancestors evolved originally from lobe-finned fish but, today, all such fish are fully aquatic. Within the blenny family, however, are species that are either highly terrestrial, amphibious or entirely aquatic. Remarkably, representatives of all these types can be found on or around Guam, making it a unique evolutionary laboratory."
Bob Beale | EurekAlert!
Diagnoses: When Are Several Opinions Better Than One?
19.07.2016 | Max-Planck-Institut für Bildungsforschung
High in calories and low in nutrients when adolescents share pictures of food online
07.04.2016 | University of Gothenburg
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
24.10.2016 | Earth Sciences
24.10.2016 | Life Sciences
24.10.2016 | Physics and Astronomy