Rainforest regeneration rescues bat communities in aftermath of fragmentation

Rainforest loss is fuelling a tsunami of tropical species extinctions. However, not all is doom and gloom. A new study, conducted in the Brazilian Amazon, suggests that ecological cataclysms prompted by the fragmentation of the forest can be reverted by the regeneration of secondary forests, offering a beacon of hope for tropical forest biodiversity across the world.

Credit: Mark Moffett/ Minden Pictures/National Geographic Stock

The international team of researchers found that species strongly associated with primary forest were heavily depleted after 15 years of man-made disruption including the burning and clearing of forest stands,

However, 30 years down the line, and with the regeneration of secondary regrowth, many of the species that had abandoned the area had made a comeback.

"If you compare the time periods, it is apparent that taking a long-term view is paramount to uncovering the complexity of biodiversity in human-modified landscapes," said senior researcher Dr. Christoph Meyer, lecturer in global ecology and conservation at the University of Salford.

The study, published in Nature: Scientific Reports, measured the impacts of forest break-up of 50 species of bat (approx. 6,000 animals).

Bats comprise roughly one fifth of all mammal species and display wide variation in foraging behaviour and habitat use, making them an excellent model group for the research.

"The responses exhibited by bats offer important insights into the responses of other taxonomic groups." says Ricardo Rocha, lead author of the study from the University of Lisbon.

"The recovery that we have documented mirrors the patterns observed for beetle and bird communities within the Amazon.

"These parallel trends reinforce the idea that the benefits of forest regeneration are widespread, and suggest that habitat restoration can ameliorate some of the harm inflicted by humans on tropical wildlife", he adds.

The results of the current study contrast with the catastrophic faunal declines observed during a similar time window in rodent communities in the 'forest islands' of the Chiew Larn reservoir in Thailand.

"The recovery observed at the Amazon was mostly due to the recolonization of previously deforested areas and forest fragments by old-growth specialist bats. This recolonization is likely attributable to an increased diversity and abundance of food resources in areas now occupied by secondary forest, fulfilling the energetic requirements of a larger set of species", explains Rocha.

However, the short-term nature of most studies has substantially impaired the capacity of researchers to properly capture the intricate time-related complexities associated with the effects of forest fragmentation on wildlife.

Source: University of Salford [February 28, 2018]

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Geological change confirmed as a factor behind the extensive diversity in tropical rainforests

The tropical rainforests of Central and South America are home to the largest diversity of plants on this planet. Nowhere else are there quite so many different plant species in one place. However, the entire region is increasingly threatened by human activity, which is why researchers are stepping up their efforts to record this astonishing biodiversity and find out how it developed. In a project undertaken by Johannes Gutenberg University Mainz (JGU) in collaboration with Dutch research institutions, the causes of this plant diversity were investigated by studying two closely related groups of trees of the Annonaceae family.

Cremastosperma brevipes, French Guiana [Credit: Paul J. M. Maas]

The researchers identified three relevant factors: the formation of the Andes mountain range, the disappearance due to natural causes of the extensive Pebas wetlands system that once existed in the Amazon region, and the formation of a land bridge between Central and South America in the form of the Panama Isthmus.

Cremastosperma and Mosannona are two genera of the Annonaceae or custard apple family the habitat of which is neotropical rainforests, where they extend from the lowlands up to elevations of 2,000 meters. They are primarily found in the Andes region of South America, but also as far north as Central America.

Mosannona costaricensis, Costa Rica [Credit: Reinaldo Aguilar]

The team of botanists led by Dr. Michael Pirie, who joined JGU as a researcher in 2013, looked at the distributions of the various species of both genera and their phylogenetic history in order to determine the influence of the geological upheavals on the continent.

For this purpose they compiled a time-calibrated phylogenetic tree based on DNA data, using the so-called molecular clock technique which is calibrated using the ages of the available fossils. In total, they analyzed 11 species of the genus Mosannona and 24 species of the genus Cremastosperma.

Formation of the Andes, the Isthmus of Panama, and the drying-out of the Pebas wetland system all promoted diversification

The research has produced a biogeographical scenario that confirms in this context the significance of the geological history of north-western South America during the late Miocene and early Pliocene periods about 5 to 10 million years ago.

Cremastosperma yamayakatense, Peru [Credit: Michael Pirie]

"We have actually discovered that the diversification of these two plant genera took place in parallel with major geological events, namely the formation of the Andes, the drying-out of the Pebas system, and the development of a land bridge to Central America," explained Pirie. Cremastosperma species, for example, were able to spread into what is today the Amazon basin and diversify, once the wetlands had silted up due to the deposition of material from the rising Andes.

One way in which diversification can be stimulated is by migration into a new ecosystem while another is adaptation to new conditions. "Natural changes over longer periods provide plants with a chance to adapt," added Pirie. On the other hand, rapid changes, such as those that have occurred in the recent past, do not give plants sufficient time to evolve.

Cremastosperma leiophyllum, Bolivia [Credit: Lars W. Chatrou]

While the development of the two genera in line with geological conditions could be said to be more or less as might be expected, the biologists did find one clear difference between them. Although their distribution patterns mostly overlap, Cremastosperma species and Mosannona species to some extent dispersed along differing routes. In the case of Cremastosperma, colonization of an area in what is now Guyana began from north-western South America at a time before the last parts of the Andes developed and could form a barrier. Mosannona, on the other hand, began to spread here at a far later date from its base in the Amazon basin.

Taxonomic update to include five new species

Dr. Michael Pirie will be continuing his research work in 2018 with the aid of a grant from the Heisenberg Program of the German Research Foundation (DFG). This will also involve publication of an extensive monograph in which a total of 34 Cremastosperma species will be described, including five new species that Pirie and his colleagues have recently discovered.

The study is published on Royal Society Open Science.

Source: Universitat Mainz [Febraury 26, 2018]

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Why are there so many types of lizards?

Lizards have special superpowers. While birds can regrow feathers and mammals can regrow skin, lizards can regenerate entire structures such as their tails. Despite these differences, all have evolved from the same ancestor as lizards.

The Anolis auratus is one of several lizard species studied as part of new research comparing lizard genomes - their entire
DNA code - to those of other animals [Credit: Kenro Kusumi]

Spreading through the Americas, one lizard group, the anoles, evolved like Darwin's finches, adapting to different islands and different habitats on the mainland. Today there are more than 400 species.

Constructing a family tree for three lizard species collected in Panama at the Smithsonian Tropical Research Institute (STRI) and a fourth from the southeastern U.S., scientists at Arizona State University compared lizard genomes -- their entire DNA code -- to those of other animals.

The researchers discovered that changes in genes involved in the interbrain (the site of the pineal gland and other endocrine glands), for color vision, hormones and the colorful dewlap that males bob to attract females, may contribute to the formation of boundaries between species. Genes regulating limb development also evolved especially quickly.

"While some reptiles such as tortoises changed remarkably little over millions of years, anole lizards evolved quickly, generating a diversity of shapes and behaviors," said Kenro Kusumi, corresponding author and professor at ASU School of Life Sciences. "Now that sequencing entire genomes is cheaper and easier, we discovered molecular genetic evidence for rapid evolution that may account for striking differences between bodies of animals living in different environments."

Kusumi's lab, working with colleagues at the University of Arizona College of Medicine-Phoenix, is especially interested in how reptiles' genomes shape their ability to regenerate and to develop a diversity of body forms.

"This is the first time the complete genetic code -- the genome -- of any vertebrate species from Panama has been sequenced and analyzed," said Oris Sanjur, co-author and Associate Director for Science Administration at STRI. "Information from these three species is an important contribution to our understanding of biodiversity and the evolution of new species."

The Anolis apletophallus is one of several lizard species studied as part of new research comparing lizard genomes - their
entire DNA code - to those of other animals [Credit: Kenro Kusumi]

Scientists estimate that there are 40 species of anolid lizards living in Panama, compared to only one in the U.S. A team from ASU collected three species with permission from the Ministry of the Environment, MiAmbiente: the Central American giant anole, Anolis frenatus, lives high on tree trunks; the grass anole, A. auratus, perches on bushes or on grassy vegetation and the slender anole, A. apletophallus, found only in Panama, hangs out lower on tree trunks or on the ground.

Researchers at ASU's School of Life Sciences lined up the DNA sequences of the lizards with the DNA sequences of 31 other animals: the lobe-finned fish and the four-legged animal groups that evolved from them. They also took a careful look at genes that code for proteins: more than 22,000 genes in the green anole, A. carolinensis, versus approximately 20,000 identified each in A. auratus and A. frenatus and 13,000 in A. apletophallus.

One obvious explanation for a faster rate of evolution is the anole lizards' faster rate of reproduction. Anoles typically mate in their first year of life, while other reptiles take much longer to reach sexual maturity. They also breed with many other individuals so mutations that make it difficult for individuals to survive are eliminated fairly quickly.

The first and only other anole lizard to be sequenced previously was the green anole, A. carolinensis, the only anole species resident in the U.S. In that study from MIT, the A. carolinensis genome held evidence of more recent evolution and the loss of ancient repeated elements in the part of the DNA that does not code for proteins. In this sense, it was important to sequence the three Panamanian species, because the U.S. species may not be the most representative of the diverse anole group.

"For 15 years, an impressive amount of time and money poured into discovering the genomes of mammals, motivated by our drive to understand human evolution and to look for cures for disease. Even though the squamate reptiles include more than 10,000 species -- almost double the number of mammal species -- a single genome was not enough to understand the variability within this group," said the first author of the report, Marc Tollis, a post-doctoral fellow at ASU.

"By comparing these four anole lizard genomes, we're beginning to understand how one of the most diverse groups of vertebrates regenerate, develop and diversify," he added.

The study is published in Genome Biology and Evolution.

Source: Arizona State University [February 23, 2018]

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The conflict between males and females could replace the evolution of new species

New research shows that males and females of the same species can evolve to be so different that they prevent other species from evolving or colonising habitats, challenging long-held theories on the way natural selection drives the evolution of biodiversity.

Image showing variations between male and female Liolaemus nigriceps [Credit: Dr Daniel Pincheira-Donoso,
School of Life Sciences, University of Lincoln]

According to Darwin's theory of natural selection, first introduced in his book On the Origin of Species (1859), new environments such as mountains and islands with abundant food and habitats, offer species the 'ecological opportunity' to colonise an area using those resources.

New research from the UK has shown that exactly the same mechanism of evolution that creates new species also operates within the same species when males and females compete for the ecological resources available in different habitats, such as bushy areas or stony patches with abundant food. The conflict between the sexes can lead to one sex becoming bigger, more colourful or adapting to eat different food, just like a traditional process of evolution by natural selection can lead an ancestor to split into two different species.

This process of evolution between the sexes expands the biodiversity of the area - a development that evolutionary biologists previously thought only occurred when the number of different species using different resources or 'niches' increases. This new research challenges that assumption, showing that different species and different sexes of the same species can occupy these niches.

Image showing variations between male and female Liolaemus tenuis [Credit: Dr Daniel Pincheira-Donoso,
School of Life Sciences, University of Lincoln]

This new research which explored the evolution of lizards in the Chilean Andes Mountains and Argentinean Patagonia, shows that different sexes of the same species can fill niches as well, meaning new species are actively prevented from evolving. This is because there is no new environment for them to occupy - a necessary condition for new species to evolve under Darwin's theory of natural selection.

Conducted by academics from the Universities of Lincoln, Exeter and Sheffield, the study demonstrated that biodiversity can now be seen as the formation of new, different species, or, as the formation of different sexes which are distinct enough to be equivalent to different species in the way they 'saturate' ecological niches.

Dr Daniel Pincheira-Donoso, Senior Lecturer in Evolutionary Biology at the School of Life Sciences at the University of Lincoln and lead researcher on the study, said: "Our research reveals evidence for this intriguing phenomenon that the evolution of sexes within a species could replace the evolution of new species, which begins to add a new layer to our understanding of the evolution of biodiversity.

"It is important to stress that the diversity of life on our planet applies not only to the evolution of different species, but also to the independent evolution of males and females within the same species, which potentially has very important implications."

The findings have been published in the scientific journal Global Ecology and Biogeography.

Source: University of Lincoln [February 21, 2018]

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Biodiversity loss raises risk of 'extinction cascades'

New research shows that the loss of biodiversity can increase the risk of "extinction cascades," where an initial species loss leads to a domino effect of further extinctions.

Credit: Andreas Haselböck/Senckenberg

The researchers, from the University of Exeter, showed there is a higher risk of extinction cascades when other species are not present to fill the "gap" created by the loss of a species.

Even if the loss of one species does not directly cause knock-on extinctions, the study shows that this leads to simpler ecological communities that are at greater risk of "run-away extinction cascades" with the potential loss of many species.

With extinction rates at their highest levels ever and numerous species under threat due to human activity, the findings are a further warning about the consequences of eroding biodiversity.

"Interactions between species are important for ecosystem (a community of interacting species) stability," said Dr Dirk Sanders, of the Centre for Ecology and Conservation at the University of Exeter's Penryn Campus in Cornwall. "And because species are interconnected through multiple interactions, an impact on one species can affect others as well.

"It has been predicted that more complex food webs will be less vulnerable to extinction cascades because there is a greater chance that other species can step in and buffer against the effects of species loss.

"In our experiment, we used communities of plants and insects to test this prediction."

The researchers removed one species of wasp and found that it led to secondary extinctions of other, indirectly linked, species at the same level of the food web.

This effect was much stronger in simple communities than for the same species within a more complex food web.

Dr Sanders added: "Our results demonstrate that biodiversity loss can increase the vulnerability of ecosystems to secondary extinctions which, when they occur, can then lead to further simplification causing run-away extinction cascades."

The study, supported by France's Sorbonne Université, is published in the journal Proceedings of the National Academy of Sciences.

How extinction cascades work

The loss of a predator can initiate a cascade, such as in the case of wolves, where their extinction on one mountain can cause a large rise in the number of deer. This larger number of deer then eats more plant material than they would have before. This reduction in vegetation can cause extinctions in any species that also relies on the plants, but are potentially less competitive, such as rabbits or insects.

Source: University of Exeter [February 19, 2018]

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At last, butterflies get a bigger, better evolutionary tree

For hundreds of years, butterfly collecting has often inspired a special kind of fanaticism, spurring lengthy expeditions, sparking rivalries and prompting some collectors to risk their fortunes and skins in their quest for the next elusive specimen.

Researchers have produced a bigger, better butterfly evolutionary tree with a 35-fold increase in genetic data 
and three times as many taxa as previous studies [Credit: Espeland et al. Current Biology]

The result is a treasure trove of scientific information stored in the form of millions of butterfly specimens, offering insights into community ecology, how species originate and evolve, climate change and interactions between plants and insects.

But a comprehensive map of how butterflies are related to each other has been lacking -- until now.

Lepidopterists Akito Kawahara and Marianne Espeland led a team effort to produce a bigger, better butterfly evolutionary tree with a 35-fold increase in genetic data and three times as many taxa -- classification units of organisms -- as previous studies. They then calibrated the tree based on the fossil record, assigning dates to certain developmental milestones.

"We still have a long way to go, but this is the first comprehensive map of butterfly evolution," said Kawahara, associate professor and curator at the Florida Museum of Natural History's McGuire Center for Lepidoptera and Biodiversity on the University of Florida campus. "Lots of previous studies cover butterfly evolution on smaller scales -- by locality or taxon -- but surprisingly few have reached across the breadth of butterfly diversity."

Shake-ups and surprises

The team analyzed a dataset of 352 genetic markers from 207 butterfly species representing 98 percent of tribes, which are a rank above genus but below family and subfamily. Their findings paint a detailed picture of relationships between butterflies and point to some name changes.

The data confirm that swallowtails are a sister group to all other butterflies, meaning they were the first family on the butterfly family tree to branch off. But while previous literature groups swallowtails, birdwings, zebra swallowtails and swordtails together, this study shows they do not share a common ancestor, a finding supported by the fact that these butterflies feed on different host plants.

"That tells us that butterflies and plants may have evolved together," Kawahara said.

A finding that surprised Espeland, the study's lead author, is that the blues are nested within the hairstreaks.

"Both of these groups have remained quite stable through time, but our study shows that a substantial rearrangement of the classification is necessary," said Espeland, who started the project as a postdoctoral researcher at the Florida Museum and is now curator and head of the Lepidoptera section at the Zoological Research Museum Alexander Koenig in Germany.

Most blues and hairstreaks and some metalmarks have mutually beneficial relationships with ants: Butterfly larvae provide sugary nectar in exchange for the ants' protection from predators. The researchers found this association evolved once in blues and hairstreaks and twice in metalmarks.

Previous studies suggest the first butterflies date back more than 100 million years, a date this study supports. But most of the lineages that exist today originated after the mass extinction event that killed off non-avian dinosaurs about 65 million years ago.

"It is actually quite nice that the ages inferred in this study are relatively similar to those found in previous studies since this means that we are gradually converging towards a consensus, which should be close to the correct ages," Espeland said.

One curious finding, Kawahara said, is that the phylogeny suggests butterfly-moths -- the only butterflies known to be nocturnal -- developed hearing organs before bats, their primary predator, appeared.

"I'm fascinated by the timing of when these hearing organs developed and why," Kawahara said. "There's a lot of mystery and uncertainty here."

He pointed to the value of the McGuire Center, home to one of the world's largest collections of butterflies and moths, in providing the data necessary -- especially from rare specimens -- for the study.

"The collections at the McGuire Center made this possible," he said. "There are probably only a few other research institutions in the world that would be able to carry this project."

Childhood dream

Like many butterfly enthusiasts, Kawahara developed the obsession early. By age 5, he had a tiny collection and could differentiate various groups of butterflies. He used his mother's Xerox machine to photocopy a simple butterfly phylogeny to help him identify specimens, posting it to the wall of his bedroom.

"It was a really boring-looking picture, gray with lines on it," he said. "I didn't know anything about evolutionary trees, but I was mystified by the unknown. A lot of the lines were dashed -- there were clearly discoveries to be made. I remember looking at it and just thinking, 'It would be really amazing to be able to study this one day.' "

An even bigger tree

The researchers have set their sights on an even more comprehensive phylogeny, one that accounts for every described butterfly species. Generating this tree is the main goal of the U.S. National Science Foundation-funded ButterflyNet project, which will organize all butterflies based on how they are related to one another. For each species, the project will include associated data such as its geographical distribution, host plants and life history traits.

"This tree represents 207 species out of some 18,800," Kawahara said. "So, it's a tiny, tiny fraction. But it's the first step."

The study was published in Current Biology.

Author: Natalie van Hoose | Source: Florida Museum of Natural History [Februaty 15, 2018]

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Action plan released to conserve one of Africa's richest sites for biodiversity

A team of scientists led by WCS (Wildlife Conservation Society) has developed a conservation blueprint to protect one of the most biodiverse regions in Africa: the Albertine Rift, home to mountain and Grauer's gorillas, golden monkeys, chimpanzees, elephants, and 162 vertebrate, and 350 plant species unique to this region.

Grauer's gorilla. A team of scientists led by WCS (Wildlife Conservation Society) has developed a conservation blueprint
 to protect one of the most biodiverse regions in Africa: the Albertine Rift, home to mountain and Grauer's gorillas,
golden monkeys, chimpanzees, elephants, and 162 vertebrate, and 350 plant species unique to this region
[Credit: A.J. Plumptre]

Based on work by WCS and participants from five countries in the region, the "Conservation Action Plan for the Albertine Rift" summarizes the results of 16 years of research and commitment to the conservation of six key landscapes within the Albertine Rift, which runs through five countries (Uganda, Democratic Republic of Congo, Rwanda, Burundi, and Tanzania) and stretches from the southern tip of Lake Tanganyika to the northern tip of Lake Albert

Building on an initial framework plan developed in 2004, the new plan highlights the importance of the region for global biodiversity and goes further to outline the main steps required for the conservation of each landscape. The plan assesses where within each landscape is most important for the conservation of the many unique and threatened species, both now and under projected climate change, and identifies which species remain unprotected.

"The Albertine Rift is the most important site for vertebrate conservation in Africa, with more endemic and globally threatened vertebrates than any other region of the continent," said Dr. Andy Plumptre, Senior Scientist for WCS's Africa program. "We know of 163 terrestrial vertebrates that are unique to this region and we keep discovering new species. We also know the lakes in this region have incredible fish diversity and that at least 350 species of plant are unique to the region."

WCS has conducted surveys of the biodiversity of the Albertine Rift over decades, supporting surveys of some species and specific sites as early as 1959 in the case of eastern gorillas (one of the endemic species). A more comprehensive program started by WCS in 2000 compiled region-wide data on mammals, birds, reptiles, amphibians and plants. WCS worked with other NGO partners and the environmental protection authorities of Burundi, the Democratic Republic of Congo, Rwanda, Tanzania, and Uganda to identify six key landscapes and to establish cooperative protection at ground-level in each.

Based on work by WCS and participants from five countries in the region, the 'Conservation Action Plan for
the Albertine Rift' summarizes the results of 16 years of research and commitment to the conservation of six key
 landscapes within the Albertine Rift, which runs through five countries (Uganda, Democratic Republic of Congo,
Rwanda, Burundi, and Tanzania) and stretches from the southern tip of Lake Tanganyika
to the northern tip of Lake Albert [Credit: WCS]

Threats to the landscapes are substantial because this part of Africa also contains some of the highest human population densities on the continent. Habitat loss is the most critical threat for most of the species. Modeling work described in the report showed that the endemic and threatened species have already lost on average 40 percent of suitable habitat to agriculture. Climate change is likely to drastically reduce the remaining suitable habitat.

"We predict that by the end of this century, endemic species will further decline in response to climate change as many of these species will need to move to higher elevations as the climate warms. These up-slope movements will result in a dramatic 75 percent reduction in suitable habitat," said Sam Ayebare, a conservationist for WCS Uganda.

Many of the areas currently under protection are essential for the conservation of these species. Three additional areas, totaling over 10,000 square kilometers, that were gazetted in 2016, Itombwe, Ngandja and Kabobo Reserves, were critical for protecting many additional endemic species, both now and under future climate change. The report assesses the optimum ways to conserve these endemic and globally threatened species, and identifies which areas not currently under protection remain important for the conservation of some of the species.

"These critical sites outside of the existing protected areas mostly occur in DR Congo," said Deo Kujirakwinja, Technical Advisor for WCS in DR Congo. "We need to focus our attention on these sites before they, and the unique species they contain, are lost."

Supporting the conservation and management of the six landscapes within the Albertine Rift will require a dedicated effort from governments and from the conservation community. However, investment in conservation in this region yields tremendous value because of its incredible species richness.

Available at: www.albertinerift.org

Source: Wildlife Conservation Society [February 15, 2018]

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Rapid evolution of a calcareous microalgae

When simulating future environmental conditions researchers face a problem: laboratory experiments are easy to control and to reproduce, but are insufficient to mimic the complexity of natural ecosystems. In contrast, experiments under real conditions in nature are much more complicated and difficult to control. Scientist of the GEOMAR Helmholtz Centre for Ocean Research Kiel have combined both approaches to investigate the response of a major plankton species to increasing ocean acidification.

Emiliania huxleyi cells in an electron microscopic picture
[Credit: Lennart Bach, GEOMAR]

The concentration of carbon dioxide (CO2) in the atmosphere increases continuously. As a consequence, an increasing amount of CO2 dissolves in the ocean, where it reacts to carbonic acid and acidifies the seawater. As ocean acidification progresses steadily, scientists aim to assess the implications of this process for marine ecosystems.

A team of researchers from the GEOMAR Helmholtz Centre for Ocean Research Kiel has for the first time examined the adaptability of the calcified alga Emiliania huxleyi to ocean acidification in a combination of laboratory and field experiments. "Some of the algae lineages in the experiment showed an extremely rapid change in their ecological fitness. We did not expect that to happen," says lead author Dr. Lennart Bach from GEOMAR. The study has been published recently in the international journal Nature Ecology and Evolution.

The current experiments were preceded by years of laboratory tests with Emiliania huxleyi at the GEOMAR in Kiel. Dr. Kai Lohbeck, co-author of the new study, had been keeping the algae under increased CO2 concentrations. Three years later, it became apparent that Emiliania huxleyi coped better with acidification than at the beginning of the experiment. "For us, that was a clear indication for the adaptability of the algae. But the experiment took place under laboratory conditions. Therefore, the question remained whether the evolutionary adaptation during an isolated lab experiment would bring an advantage also under natural conditions," says Lohbeck.

The opportunity to investigate this question emerged in the spring of 2013. The research group of Professor Ulf Riebesell conducted experiments with the Kiel Offshore Mesocosms in the framework of the collaborative project BIOACID (Biological Effects of Ocean Acidification) on the influence of ocean acidification on natural communities in Gullmarsfjord in Sweden. From the laboratory in Kiel, some of the already adapted algae cultures as well as the associated control groups were taken along to Sweden. There, they were added to the plankton communities which were acclimated to high CO2 levels in the field experiments.

"To our surprise, we found that the algae lineages that had already been adapted to ocean acidification in the lab did not cope any better at lower pH levels than the control groups that had never experienced acidification before," says Dr. Bach. An equally surprising finding: Although all algal lineages had the same ancestors, they differed significantly in their ability to compete in the natural plankton community after only three years. While some lineages proliferated rapidly, others tended to be excluded from the natural community, regardless of whether or not they were previously adapted to ocean acidification. "This demonstrates Emiliania huxleyi's ability to evolve rapidly," Bach resumes the results of the study.

Prof. Riebesell, co-author of the study and coordinator of the BIOACID project, sees this as an indication of how little we understand the long-term effects of ocean acidification: "The organisms' ability to adapt to new environmental conditions surprises us again and again. However, it does not change the fact that as ocean acidification progresses, many species will be unable to maintain their ecological niches. The loss of biodiversity is therefore inevitable."

Source: Helmholtz Centre for Ocean Research Kiel (GEOMAR) [February 14, 2018]

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