The very first research study to take a gander into what kind of biological activity there is in the deepest part of the ocean crust has turned up bacteria with an astonishing range of abilities, which include eating oil, natural gas, and “fixing” or storing carbon.

This new study, which was recently released in the journal PloS One, has demonstrated that a vast number of bacterial lifeforms were thriving, even when the temperatures reached the boiling point of water.

“This is a new ecosystem that almost no one has ever explored,” commented a professor in the College of Oceanic and Atmospheric Sciences at Oregon State University, Martin Fisk. “We expected some bacterial forms, but the long list of biological functions that are taking place so deep beneath the Earth is surprising.”

The Oceans crust cover close to seventy percent of the surface of our planet and it’s geology has been explored to a certain degree, however no one has bothered to look into its biology – because it is hard to do, and very costly, but also because most scientists have always taken it for granted that nothing was happening down there.

The temperatures rise exponentially as you get deeper – as any high school graduate can tell you – and researchers now think that the maximum temperatures which can harbor life are at about 250 degrees.

So, now you know, when we think we know something about the world – such as boiling water kills bacteria – we are thrown a curve ball. However, the discovery that some of these organisms like to eat oil is very exciting indeed.

In several species of fish, such as the cichlid species Neolamprologus pulcher, it is common for subordinate females to help an unrelated dominant breeding pair raise their young. The reason behind this seemingly altruistic behaviour, known as alloparental care, has puzzled scientists for many years and one of the most widely spread hypotheses put forward has been the ‘pay-to-stay’ hypothesis. According to the ‘pay-to-stay’ rationale, the subordinate female helps out the dominant pair just to be able to stay in the group. Not being ostracised from the group augments her long-term survival chances, thus increasing the chance for her to live long enough to eventually obtain a breeding position.

Picture by: JJPhoto.dk

A new study carried out by Dik Heg and coauthors does however bring forth a new hypothesis: the substrate rationale. In their study, Heg and his colleges tested the hypothesis that subordinate female cichlids are helping dominant pairs in return for a more immediate direct reproductive benefit. After a series of experiments where the total number of eggs produced over a 30 day period by dominant and subordinate Neolamprologus pulcher females were carefully counted, researchers found that a subordinate female helping out a dominant pair was more likely to produce eggs herself compared to other subordinate females.

According to Heg and coauthors, the most likely reason for the increased reproductive success of “fish nannies” is that the subordinate female gains access to the breeding substrate.

If you wish to read more, see the paper “Heg, D, E Jutzeler, JS Mitchell and IM Hamilton (2009) Helpful female subordinate cichlids are more likely to reproduce”. It has been published in the journal PLoS ONE.

Here at AC Tropical Fish, we believe in the Jude Law-hypothesis. The dominant female will naturally snatch away the most prosperous male, but by posing as a benevolent nanny even a subordinate female can gain access to his home and hope for some of his triumphant DNA to eventually find its way into the genetic make up of her own offspring.

As reported earlier, fish populations may adapt and change in response to significant fishing pressure. Researchers are now suggesting that the genetic make-up of cod in the Atlantic Ocean might be changing, since cods genetically predisposition to seek out shallower waters are more likely to end up in nets or on fishing lines, while deep-dwellers are more likely to survive and reproduce.

If the current over-fishing of shallow living cod is not put to an end, evolutionary biologist Einar Árnason and his colleagues believes the genetic variant found in shallow-living cod will be lost all together. If the deep-water cods do not spread into the shallows, and Árnason doubts they will since they are adapted to deep water conditions, the shallows may be become devoid of cod within the next 10 years. This will decrease the size of the total cod population and will also force the fishing industry to either give up cod fishing altogether or switch to expensive deep-water trawling.

Árnason and his colleagues have studied cod populations off the coast of Iceland, where fish stocks are still in fairly decent condition compared to the severely depleted populations found in the western Atlantic. In their study, the researchers examined how the genotypes of Icelandic cod have changed between 1994 and 2003.

It was already known that cod living in the Icelandic shallows have a different variant of the pantophysin I gene than the cods found at much larger depts. In their study, Árnason and his colleagues found that the shallow-water variant of pantophysin I is becoming increasingly rare; a change which they attribute to the fact that most Icelandic cod fishers work in shallow waters near the coastline using lines and nets instead of carrying out deep-water trawling.

Árnason and his team also found that Icelandic cod are reaching sexual maturity at a younger age and at a smaller size than before. This is discovery is a chilling revelation for Icelandic fishermen and conservationalists alike, since that was exactly what happened in Newfoundland waters before that cod population crashed completely.

The study has been published in the journal PLoS ONE

Good news from Queensland: Certain reefs in Australia’s Great Barrier Reef Marine Park seem to have undergone a remarkable recovery since the devastating Keppel Islands coral bleaching event of 2006.

In 2006, massive and severe coral bleaching occurred around the Keppel Islands due to high sea temperatures. After being bleached, the reefs rapidly became overgrown with a species of seaweed and scientists feared this would be the end of the corals.

Picture is not from Keppel Island. It is another part of the Great barrier reef

Earlier studies have indicated that reefs that do manage to recover from catastrophes like this one need at least a decade or two to bounce back. However, a lucky combination of three previously underestimated ecological mechanisms now seems to have made it possible for the Keppel Islands reefs to make an amazing recovery, with large numbers of corals re-establishing themselves within a single year.

“Three factors were critical,” says Dr Guillermo Diaz-Pulido, from the Centre for Marine Studies at The University of Queensland and the ARC Centre of Excellence for Coral Reef Studies (CoECRS). “The first was exceptionally high regrowth of fragments of surviving coral tissue. The second was an unusual seasonal dieback in the seaweeds, and the third was the presence of a highly competitive coral species, which was able to outgrow the seaweed.“

Dr Diaz-Pulido also stresses that the astonishing recovery took place in a well-protected marine area where the water quality is at least moderately good.

Surviving tissue, not sexual reproduction

“The exceptional aspect was that corals recovered by rapidly regrowing from surviving tissue,” explains Dr Sophie Dove, also from CoECRS and The University of Queensland. “Recovery of corals is usually thought to depend on sexual reproduction and the settlement and growth of new corals arriving from other reefs. This study demonstrates that for fast-growing coral species asexual reproduction is a vital component of reef resilience.”

Buying time

According to Professor Ove Hoegh-Guldberg, also of the CoECRS and The University of Queensland, understanding the different mechanisms of resilience will be critical for reef management under climate change. “Clearly, we need to urgently deal with the problem of rising carbon dioxide in the atmosphere, but managing reefs to reduce the impact of local factors can buy important time while we do this. Our study suggests that managing local stresses that affect reefs, such as overfishing and declining water quality, can have a big influence on the trajectory of reefs under rapid global change.”

Dr Laurence McCook from the Great Barrier Reef Marine Park Authority agrees. “As climate change and other human impacts intensify, we need to do everything we possibly can to protect the resilience of coral reefs. This combination of circumstances provided a lucky escape for the coral reefs in Keppel Islands, but is also a clear warning for the Great Barrier Reef.“

You can find out more about the remarkable recovery in the paper “Doom and boom on a resilient reef: Climate change, algal overgrowth and coral recovery”, published in the journal PLoS ONE, by Guillermo Diaz-Pulido, Laurence J. McCook, Sophie Dove, Ray Berkelmans, George Roff, David I. Kline, Scarla Weeks, Richard D. Evans, David H. Williamson and Ove Hoegh-Guldberg.

A group of scientist from UK, Australia, the US, Sweden and France are arguing that we need to rethink how we protect our marine environment if we want to protect our reefs. The way we protect vulnerable areas today will not suffice to save the coral reefs from the threat of global warming.

The type of small protected areas that we use today were designed by researchers in the 60s and 70s and is good to prevent species from going extinct due to fishing etc but are not enough to protect against the treats reefs are facing today like global warming. This is the conclusion they have reached after extensive studies carried out in over 66 sites across seven countries over more than a decade. The team has published their result in the journal PLoS ONE. The study is the biggest of its kind done to date.

It is however important to stress that they don’t think the present protected areas are to be removed or that new such areas shouldn’t be protected. What they are saying is that this work has to be complemented with a new type of protected areas that need to be located in the right places.

Lead researcher Nick Graham, of Newcastle University’s School of Marine Science and Technology, said: “We need a whole new approach – and we need to act now.

The research the scientist did shows that the location of the protected areas are very important and that many of the world’s existing protected areas are in the wrong place to protect the reefs. New protected areas need to be setup in new locations and the focus need to change from protecting small areas to protecting entire reef systems. It is important to minimize the human impact on the reefs from actions such as over-fishing, pollution and sedimentation as coral dies if they are put under to much stress. If we remove other sources of stress the reef becomes more likely to survive the stress caused by increased water temperature caused by global warming.

Although the research seems to show a grim future with a lot of reef being damaged and showing signs of long-term degradation there were also good signs with some reefs remaining healthy or even recovering from earlier damages.