Well-BeingNatural science through studying crabs

This story is about three young men working on crab research. They became interested in nature when they were younger and started researching crabs when they were all in junior high school. Over the years they have won several science awards and they are now focusing their work on deeper themes. Their activity base is the Lab. ORCA science experiment class in Hiroshima, and their research is supported by Manai Institute of Science and Technology that support junior and high school students, in a form of a subsidy called the Manai Grant. In addition, this article introduces the Nikon microscopes that are utilized for the young scientists' everyday research.

Deep and keen insight into crabs through determined research

Even well-known Nobel Prize scholars need to spend years accumulating data and progress through academic benchmarks. Today, young enthusiastic scientists all over the world are working on their own research while building their futures as well. Naotaro Ishikawa, Fukuto Tagami, and Rei Kano are researching crabs in the science experiment class Lab. ORCA in Hiroshima city.
They have participated in tidal flat observation workshops since they were kids and became interested in crabs. Later, they began full-scale research as a team starting in their junior high school years. The theme of their research is to discover how the crabs living on tidal flats and land environments have adapted from underwater habitats. To reveal this process, for several years they have been studying the correlation between the distribution of various types of crabs and the number of their gills, which are their respiratory organs, and levels of resistance to drought.

From left to right: Rei Kano, Naotaro Ishikawa, and Fukuto Tagami

This all began from the three young men's discussions and subsequent hypothesis development.
In order to prove their hypothesis, they accumulated vast amounts of research through such means as collecting crabs, dissections, and then classifying and recording the gills.
This hard work was achieved through deep, keen insights and consistent daily efforts – often referred to as “the royal road of science." As a result, they have won several accolades such as the Hiroshima Science Award and the Japan Student Science Award.

Lab. ORCA is located close to Nishi Hiroshima station on the JR and Hiroshima Electric Railway
The tidal flats of the Ota River discharge channel, which is close to Lab. ORCA, where Ishikawa, Tagami, and Kano conduct their main fieldwork
A Helice tridens crab collected on the tidal flats
Diagram of photographed and classified ghost crab gills (published in the paper)
Diagram summarizing the number of crab gills

Supporting the passions of future researchers

At Lab. ORCA, many students besides Mr. Ishikawa and his two partners are seriously pursuing research in biology, physics, chemistry, and other advanced fields. Mr. Mitsuo Kuya, the head of Lab. ORCA, inspires each student who visits the lab and continually motivates them to study independently into the future. One day, Mr. Kuya found that there was a system to support junior and high school students' research on science and technology through subsidies. This program is run by a foundation that is a part of MANAI, a company which aims to serve as a community base for junior and senior high school students around the world to conduct scientific research. Mr. Kuya recommended to Mr. Ishikawa and his colleagues that they should apply for the Manai Grant to assist in furthering their research.

Workshop held at MANAI's Ichigaya base in Tokyo

Out of the many applications received for the Manai Grant from junior and senior high school students around the world, the crab research team was ultimately selected. Ryuichi Nomura, a representative of MANAI, explains the reason, “What captured my heart the most was their enthusiastic attitude toward working on this project. I could sense something that only young researchers can look forward to in their future lives." Mr. Nomura continued to expound, “People can only effectively learn through immersive devotion to their work", a universal truth realized from his own experiences of devoting himself to research while at high school. This adage is also the philosophy that drives MANAI's activities and its hopes for junior and high school students to generate self-motivated passions for learning. As MANAI's hopes and the proactive approach the crab research team displayed naturally overlapped, this was the main reason for their selection.

Certificates of the Manai Grant sent to Ishikawa, Tagami, and Kano
Ryuichiro Nomura of MANAI

Nikon stereo microscopes that support research with their ease of use and viewing

Using the Manai Grant, Mr. Ishikawa and his team were given the stereo microscopes*1 (Nikon SMZ745) that are essential for advanced future research. After employing these new microscopes, they reported that the observation and dissection of crabs for their research have been taken to a whole new level.
At the lab, the research team first dissect the crabs that have been fixed and stored in alcohol after being put to sleep in a freezer. There are various types of crabs selected, ranging in size from 3-4cm or larger to specimens of less than 1cm. Next, only the gills are removed from the dissected crabs. There are usually eight or nine pairs of gills integrated with the jaws, claws, and legs, so all the parts must be removed and separated. The work up to this point is performed utilizing stereo microscopes.
“The new microscopes have a wide stage and the working distance*2 has increased from 77.5mm to 115mm, so even large, thick crabs can be easily observed and dissected," Mr. Ishikawa explains. Mr. Tagami continued, “The magnification has increased from 5x to 7.5x, so the dissection of small crabs, which I had a hard time with until now, has become much easier." Mr. Kano added, “The field number*3 has expanded significantly from 18mm to 22mm, so that made the work much easier. I also like the microscopes' simple design."
And the common thought of these three young men who use this microscope was that “being able to observe things that have never been seen before will expand the scope of research, which may lead to new discoveries."

Research using the SMZ745 in the lab
Dissecting crabs while observing through the SMZ745
Setting the classified gills on the petri dish to be photographed
A digital camera equipped with a macro lens is used for taking photographs

After using the microscopes for separation, the gills are then lined up in a petri dish to be photographed. A special table is set up for taking photos utilizing a digital camera fitted with a macro lens, employed for close-up photography, to shoot the observation subjects. Ishikawa, Tagami, and Kano share their work and efficiently perform the tasks, displaying a keen sense of understanding through their perseverance toward effectively achieving comprehensive research methods.

Left: Stereo microscope used up till now
Right: New Nikon SMZ745 stereo microscope
Image taken with the Nikon SMZ745T stereo microscope: Gills of a ghost crab
(Dye and focus stacking are applied after shooting)
Shooting and image courtesy: Mitsuo Kuya of Lab. ORCA
Image taken with the Nikon SMZ745T stereo microscope: Absorptive hair of a ghost crab
(Focus stacking is applied after shooting)
Shooting and image courtesy: Mitsuo Kuya of Lab. ORCA

“Throughout our experience, we have learned how to properly conduct research. We discovered issues from various literature and through daily observations, discussed thoroughly how to solve them, then made predictions and provisions. We then solved any problems that presented by repeating our observations and experiments. By repeating these processes, we can also take on new challenges and obtain results. I want to make full use of this experience in the future," Mr. Ishikawa explained. Just like him, Mr. Tagami and Mr. Kano who have been working together for several years are also looking at the path they should take in the future using their own will.

Young, passionate researchers who look deeply into the wonders of nature are able to think from fresh perspectives and thus open up novel discoveries through their persistent research. Nikon hopes to contribute to their efforts through the use of its microscope technology.

  • *1Stereo microscopes are instruments that can capture an observation target three-dimensionally for both eyes. The microscope image is upright.
  • *2The working distance is the distance from the tip of the objective lens to the target subject when the microscope is in focus.
  • *3The field number is the diameter of the image created by the objective lens that can be seen with the eyepieces. It is usually expressed in millimeter units.