OIST minisymposium on using advanced imaging techniques to study evolution of ant phenotypes

Last week our lab hosted an OIST Mini Symposium titled “Advances in imaging, quantifying, and understanding the evolution of ant phenotypes” organized by Evan Economo and Francisco Hita Garcia. The aim of the symposium was to gather a small but selected group of leading researchers interested in the evolution of ant phenotypes with a strong focus on the use of x-ray microtomography (micro-CT). Our list of speakers covered experts in the fields of molecular and morphological systematics, anatomy, functional morphology, comparative morphology, adaptive trait evolution, reproductive biology, linear and geometric morphometrics, and paleontology. All invitees gave outstanding talks and presented published or ongoing research in great detail and with beautiful 2D or 3D illustrations and/or videos.

Some talks provided conceptual and technical backgrounds and perspectives of how to use micro-CT for ant morphology, how to better integrate next-generation phenomics into systematics, palaeontology, and evolutionary biology, and how to use micro-CT data and downstream 3D applications for education and public outreach.

A strong focus of the symposium was the use of micro-CT for ant functional morphology, biomechanics, and the evolution of complex phenotypes. Some guests also showed recent advances in histology-based anatomy and reproductive biology, and shared ideas of how to combine traditional histology with modern 3D imaging technologies, such as micro-CT.

We also had a session focusing on the use of 2D linear and 3D geometric morphometrics and their application for ant phylogenetics, taxonomy, trait evolution, and more generally how to use large 3D phenotypical datasets to answer questions in evolutionary biology.

One afternoon was completely devoted to practical demonstrations of how to use 3D data. Our lab shared how we scan data post-processing, 3D virtual reconstructions, 3D animations, virtual/augmented reality, 3D printing. It was useful for sharing knowledge of methodology, and stimulating ideas for future directions and applications.

The three-day symposium provided ample opportunities for socializing and chatting about on-going and potential collaborations, discussions about methods and research results, as well as brainstorming about future directions for the field. At the same time our invitees got the chance to enjoy Japanese and Okinawan culture and cuisine and show off their Karaoke skills.

Invited speakers:
Phil Barden (New Jersey Institute of Technology)
Johan Billen (KU Leuven)
Benjamin Blanchard (U. Chicago and Field Museum)
Ayako Gotoh (Konan U.)
Yoshiaki Hashimoto (U. Hyogo, Museum of Nature and Human Activities, Hyogo)
Fuminori Ito (Kagawa U.)
Roberto Keller (Museu Nacional de História Natural e da Ciência)
Andrea Lucky (U. Florida)
Christian Peeters (U. Pierre et Marie Curie)
Shauna Price (Field Museum)
Andrew Suarez (U. Illinois)

Internal speakers:
Evan P. Economo
Georg Fischer
Nick Friedman
Francisco Hita Garcia
Adam Khalife (U. Pierre et Marie Curie and OIST)

OIST Science Challenge 2018: Measuring Biodiversity

Every year OIST hosts the Science Challenge, which is organized by the Graduate School as an opportunity for Japanese undergraduate students to explore scientific career options. Over the course of a few days the students participate in a number of activities that focus on the diversity of scientific paths and introduce ways to develop the international communication skills necessary for success.

The Biodiversity and Biocomplexity Unit organized a hands-on activity for the 2018 science challenge. Twelve students signed up, making the “Measuring Biodiversity” activity the most popular at OIST for the second year in a row. The goal of the activity was to quantify the diversity of insects in a vial given a short period of time and no taxonomic expertise. This year’s students were really enthusiastic about using their observations to quantify biodiversity, and had some great ideas about how to do this at scale in the future.

Nick Friedman, Takuma Yoshida, Ayumi Inoguchi, Adam Khalife, and Georg Fischer helped out with the activity.

Listening to ecosystems: New study published using acoustic monitoring to study Okinawa’s “Soundscape”

At every OKEON site there is a small green box attached to a tree. These boxes are acoustic monitors, and they are recording natural sounds almost constantly. As part of the OKEON project, we use these natural sound recordings, or “soundscapes”, as a way of monitoring biodiversity.

Sam Ross sets up an acoustic monitoring device at the OIST field site.

We collect more than 1 terabyte of audio data every week. If you wanted to listen to all of the recordings we’ve made so far, it would take you about 8 years… if you listened all day and never went to sleep. To sort through all this audio data, we use two approaches. First, we break the sounds up into sounds at different frequencies (i.e., pitch). This lets us get a big picture view of when and where animals are active on Okinawa. Second, we use machine learning to train our computers to detect species in which we are interested. This helps us understand more about which particular species are in each area of the island, and how their behavior varies across the year.

In many parts of Okinawa, humans and nature live close together. Managing this interaction is important for preserving wild populations of plants and animals.

Ultimately, our project aims to understand the ways that human activity affects Okinawa’s wildlife, and how we can better protect these species in the future. For more information (including videos), please see the OIST press release. A link to the study can be found here.

OKEON Churamori Project Symposium 2017

On Saturday, July 29th, many collaborators of the OKEON Churamori Project along with the general public gathered at OIST to attend the OKEON Churamori Project Symposium 2017. This event was the project’s first symposium and it was a great success, with over 170 attendees, interesting and informative talks, a panel discussion, and a post-symposium gathering that included hands-on exhibitions and a poster session where participants were able to exchange ideas.

Chillier Winters, Smaller Beaks

This honeyeater (Melidectes belfordi) lives in the montane forests of New Guinea. Photo credit: Charles Davies; Flickr. This photo was cropped from the original version.

(Article provided by the OIST media section)

Although Charles Darwin lived and worked in the 19th century, modern evolutionary biologists are far from exhausting all avenues of inquiry regarding birds and evolution. For example, in the 1990s, researchers such as Russ Greenberg, ornithologist from the Smithsonian Institution in the United States, began to explore a new question concerning the relationship between climate and the evolution of beak size. This question was inspired by Allen’s Rule, which states that warm-blooded animals living in cold climates will have shorter limbs and appendages than those that live in warmer climates. The biological mechanism behind this rule is thermoregulation—more body surface area helps animals to shed heat better whereas less surface area helps them to conserve it. Since a bird’s beak plays a large role in thermoregulation—it has lots of blood vessels and is not covered in feathers—researchers wondered whether hotter climates beget larger beaks and colder climates beget smaller ones. Indeed, studies revealed that climate has influenced beak size, but not which type of climate had more of an overall impact.

Past research left a question open at the end: “Which of these functions is under selection?” Dr. Nicholas Ryan Friedman, a researcher from the Biodiversity and Biocomplexity Unit at the Okinawa Institute of Science and Technology Graduate University (OIST), comments. “Are birds with small beaks dying in the summer because they get too hot? Or are birds with large beaks dying in the winter because they get too cold?” In collaboration with scientists in the Czech Republic, Dr. Friedman designed a study to explore this question and ultimately found that winter, not summer, had more of an impact. The study is published the journal Evolution.

Dr. Friedman and colleagues chose to tackle the question by recording variations in beak size in Australasian honeyeaters and allies. What makes this group of birds a great subject for this study is that the region they inhabit, Australia, New Guinea, and the South Pacific, exhibits huge variation in climate and temperature—from the tropical forests of New Guinea, to central Australia’s arid deserts, to the temperate forests of Tasmania. This means that it is possible to compare differences between individuals of the same species that are living in wildly different conditions.

After measuring the beaks from 158 different species using specimens from the Australian National Wildlife Collection and comparing beak sizes to climate, the researchers found no correlation with summer temperatures but a clear one for winter—the coldest winters were associated with the smallest beaks, whereas warmer winters were associated with larger beaks.

The top graph shows a correlation between beak size and winter minimum temperatures, with the smallest beaks relating to the coldest winters. The bottom graph shows no clear correlation for summer maximum temperatures.

Before Dr. Friedman and colleagues reported this new environmental pressure on beak size, winter temperatures, feeding habits were believed to be the greatest driving force in beak evolution. For example, since the 1970s, Peter and Rosemary Grant, the famous duo who measured the process of evolution in real-time in the Galapagos, have been studying how beak size can change due to food availability over a short period.

“Which is exciting!” Dr. Friedman comments. “But it’s not yet clear from that whether adaptation to improve feeding efficiency is the only, or even the most important, factor in driving beak evolution across millions of years.”

What is unique about Dr. Friedman and colleagues’ study is that it allowed for a peek into an unusually broad evolutionary timeframe. By comparing many different species of birds, the researchers were able to delve into a very distant past and discover the morphological importance of winter temperatures. The next step would be to better understand the relationship between these two factors—feeding efficiency and winter temperatures—in the overall narrative of beak evolution.

The Helmeted Friarbird (Philemon buceroides), a member of the honeyeaters, lives in Northern Australia and New Guinea. Photo credit: Jim Bendon; Flickr.

By Anne McGovern (media@oist.jp)