Species at the extremes of the food chain evolve faster, study says

December 17, 2018, University of Tennessee at Knoxville

Reef fish species at the extremes of the food chain—those that are strict herbivores or strict fish predators—evolve faster than fish species in the middle of the food chain with a more varied diet, according to a new study published in Nature Ecology and Evolution.

The paper, co-authored by Samuel Borstein, a Ph.D. candidate in the Department of Ecology and Evolutionary Biology, could challenge the way scientists think about evolution in relation to the position a species holds on the food chain.

Up until now, scientists thought that species that eat a wide variety of different foods might evolve quicker and show more variations in morphology—physical aspects such as size, shape, and color.

However, Borstein and his team were able to prove the exact opposite: species with the most limited diet are evolving faster.

For the study, the researchers produced an evolutionary "family tree" that describes the relationships of more than 1,500 coral reef species, their place in the food chain, and the diversity of items on which they feed.

They also digitized hundreds of photographs of reef fish to gather information on physical traits that are important for feeding, such as the depth of the peduncle (the part of the fish where body and fins attach).

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Scientists highlight 9 new reef fish species off West Papua

by Wahyu Chandra on 14 May 2018

Scientists in Indonesia have discovered nine new reef fish species in the waters off West Papua province.

The discovery highlights the importance of protecting the region’s marine ecosystem for its vast and rich biodiversity.

However, the researchers also found indications of blast fishing in the protected areas, and have called for sustainable management of the ecosystem.

Scientists in Indonesia have found nine stunning new reef fish species in the protected waters off the country’s largely untouched province of West Papua.

They collected samples of the species from 12 sites at two marine conservation zones, Berau Bay and Nusalasi Van den Bosch Bay, in the coastal district of Fakfak during a two-week field survey in March.

Continued  

Reef fish inherit tolerance to warming oceans

April 30, 2018, ARC Centre of Excellence in Coral Reef Studies

In a rapidly changing climate, the decline of animal populations is a very real concern. Today, an international team of researchers report new evidence of reef fish adjusting to global warming conditions at the genetic level.

For the first time, researchers from the ARC Centre of Excellence for Coral Reef Studies (Coral CoE) and the King Abdullah University of Science & Technology (KAUST), have found that reef fish can inherit from their parents the genetic tools to adjust to ocean warming.

"When parents are exposed to an increase in water temperature, we found that their offspring improved their performance in these otherwise stressful conditions by selectively modifying their epigenome," said senior author Prof Philip Munday of Coral CoE at James Cook University.

Epigenetic change refers to chemical modifications in the DNA that signals genes to be switched on or off. A range of factors, including disease, famine, or in the case of this research, heat stress, can stimulate these subtle changes.

In this study, when both parent and offspring experienced the same elevated water temperatures, responsive changes in their epigenome, via selective DNA methylation, were observed that enhanced the next generation's ability to cope with the new, warmer temperatures.

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Color-morphing reef fish is a ‘wolf in sheep’s clothing’

Date:

March 19, 2015

Source:

University of Cambridge

Summary:

A new study has shown that the dottyback, a small predatory reef fish, can change the color of its body to imitate a variety of other reef fish species, allowing the dottyback to sneak up undetected and eat their young.

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Ocean Acidification robs reef fish of their fear of predators

Date:

April 13, 2014

Source:

Australian Institute of Marine Science

Summary:

Research on the behavior of coral reef fish at naturally-occurring carbon dioxide seeps in Milne Bay in eastern Papua New Guinea has shown that continuous exposure to increased levels of carbon dioxide dramatically alters the way fish respond to predators. 

Continued

Violent Head-Butting Discovered in Giant Reef Fish

Scientists diving in the North Pacific were jarred when they heard mysterious sounds like spear guns being fired. The jolting noises turned out to be never-before-seen (or heard) head-butting bouts between some of the largest coral-reef fish, called parrotfish.

As they studied groups of the giant bumphead parrotfish (Bolbometopon muricatum), which can reach 4 feet (1.3 meters) long and 100 pounds (46 kg), the researchers were able to document the violent behavior with video and images.

The reef fish are named for their bulbous foreheads, which add to their eccentric, pouty lips and yellowish-to-pink faces. 

More:  http://www.livescience.com/20883-violent-head-butting-parrotfish.html

Reef fish live and hunt as a team

Yellow saddle goatfish work together to catch their dinner, according to scientists.

When an individual chases its prey around a coral formation, others gather around to block escape routes.

The unusual co-ordinated behaviour was observed by scientists in the Red Sea, off the coast of Egypt.

The discovery, published in the journal Ethology, places the fish in an elite group of species known to hunt collaboratively.

Yellow saddle goatfish (Parupeneus cyclostomus) are tropical fish found in the Indo-Pacific region, an area that is thought to be home some of the world's richest marine life.

They have long whisker-like "barbels" protruding from their mouths, which they use to detect the movements of prey in coral reefs.

Co-ordinated action
Scientists from the University of Neuchatel, Switzerland, were studying the fish to find out more about their social structure.

Read on...

By Ella Davies Reporter, BBC Nature