The European Research Council (ERC) has awarded a grant of almost two million Euros to Associate Professor Lee Hsiang Liow, for a project that aims to bridge the huge conceptual gap between microevolution and macroevolution.
“Some evolutionary scientists believe that macroevolution, generating diverse species over millions of years, is simply the sum of microevolutionary processes. We believe something else might be going on, but we do not yet know exactly what it is. I hope to discover this “something” over the five years with funding from the ERC”, says Liow. She is an Associate Professor at the Natural History Museum and the Centre for Ecological and Evolutionary Synthesis (CEES) at the University of Oslo (UiO).
Scientists who are interested in microevolution may, for instance, study how populations change over a few generations, while the study of macroevolution is more about how species and groups of species arise, evolve and become extinct over long periods. Lee Hsiang Liow’s idea was to bridge the two ways of thinking by using a group of species that could be studied in detail in terms of both macro- and microevolution.
“Many groups can be studied at both the “macro” and the “micro” level, but the somewhat obscure but incredibly beautiful bryozoans (Bryozoa) are the only group that can be studied at both levels with both living and fossil species. In addition, bryozoan fossils are often so well preserved that it is possible to study the competition among different colonies of bryozoans that lived millions of years ago. This is crucial because competition is deemed to be a very important driver in microevolution”, Liow explains.
Bryozoans are a group of largely marine, colonial animals. Although individual constituents of a colony (called zooids) are tiny, some species can form colonies of up to one meter in size. Within the colonies, each zooid resides in a small chamber, usually made of hard calcium carbonate. While most bryozoans are sessile, some unusual species have developed the ability to walk.
Bryozoans are sometimes called “moss animals” because some species can resemble a moss-like coating on rocks and other surfaces. Other species can look almost like algae or corals, but those groups are in fact very distantly related to bryozoans in evolutionary terms.
Since the first appearance of bryozoans in the fossil record about 500 million years ago, the group has expanded in diversity: there are approximately 5,000 described species of bryozoans living today. In addition, there are many more fossil bryozoans. The group has not been the focus of much scientific work, but Liow is about to change that with the help of her bryozoology colleagues.
Mapping the relations between bryozoans
Lee Hsiang Liow will use the ERC grant to figure out how living species of bryozoans are related to each other by estimating a phylogenetic tree – that is, a branching diagram that shows the “family tree” of bryozoan species. Using this “family tree”, Liow will test different ideas about how inter-species competition, reproductive rates and ecological changes relate to speciation and extinction (i.e. macroevolution).
“The fossils are not only abundant, but often so well preserved that it is also possible to see structures that can even reveal how many offspring each colony produced. This is really unique: You can’t make an accurate guess of how many babies a dinosaur had, for instance. Using fossils of bryozoans, we can also study past competition among different species: the growth of one colony over another is literally frozen in time. This possibility to observe biological interactions in the fossil record is, again, really unique”, she says.
The main objective of the project is to investigate whether changes over a few generations is important for the formation (and extinction) of species, which occur over a much longer period.
“Some biologists argue that microevolution is all that is needed to explain everything in evolution. But many palaeontologists, and perhaps also macroevolutionary biologists, believe that microevolution and ecological interactions are not that important for the grand patterns of the formation and extinction of species. This is a topic of intense debate, and I hope that my project can bring new insights”, Liow says.
– But if macroevolution is not the sum of many microevolutionary changes: What is it instead?
“We don’t know enough about this, but like I said, we believe that macroevolution is more than repeated rounds of microevolutions. For example, there is reason to believe that the properties that promote the survival of individuals (microevolution) may have negative effects in terms of the generation of new or the survival of species (macroevolution)” responds Liow.
Good things come to those who wait
Lee Hsiang Liow has lately been working on what she calls a “failed ERC project”. But the project is only a failure in the sense that her previous application didn’t result in an ERC grant. Liow’s “failed project” did result in an interview with the ERC science panel in Brussels, which is an achievement in itself. The administrators at the Research Council of Norway were so impressed that Liow was awarded a “consolation prize” for researchers with exceptionally good ERC applications, and so she was able to develop the project further.
“This was actually my third application. The moral is that you should never give up, at least not if you believe that you are onto something important”, Liow concludes.
Lee Hsiang Liow was born and raised in Singapore and has a bachelor's degree from the National University of Singapore. She earned a master's degree at Uppsala University and the Swedish Biodiversity Centre at the Swedish University of Agricultural Sciences, and then went on to the University of Chicago in the United States to earn a doctorate in evolutionary biology. She joined the University of Oslo as a postdoctoral researcher at CEES in 2006.
The fruit fly of macroevolution
“I am sure that you are familiar with fruit flies, which are “lab rats” among biologists and medical scientists. I want to establish bryozoans as "the fruit fly of macroevolution”, a model organism that can be used to integrate molecular, fossil, phenotypic, ecological and environmental data”, Liow explains.
Liow’s new funding comes from the European Research Council's scheme for Consolidators, which targets talented researchers between 7 and 12 years after they received their doctoral degrees. Applicants for this grant must demonstrate their scientific maturity and potential for independent research, according to the Norwegian Research Council’s information about the ERC scheme.
“The ERC grant is an international recognition of Lee Hsiang’s research. Her application and the research ideas are really involved, and we are thrilled by her success, says the head of the Paleontology group at the Natural History Museum in Oslo, Professor Hans Arne Nakrem.
Liows research project is titled Abiota, Biota, Constraints in Macroevolutionary Processes.
Lee Hsiang Liow et al.: Interspecific interactions through 2 million years: are competitive outcomes predictable? Proceedings of The Royal Society, Biological Sciences, 31 August 2016.
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