Those pesky little bugs flying around the overripe bananas in your kitchen may hold the key to understanding something new about how our bodies work. That’s right, the fruit fly (Drosophila melanogaster) is a widely used research organism in genetics because of its superpower of reproducing quickly with similar genes to people.
Researchers have been studying fruit flies for over a century for many reasons. First, they’re easy to please—just keep them at room temperature and feed them corn meal, sugar, and yeast (or those bananas on your counter!). Second, they reproduce more quickly and have shorter life cycles than larger organisms. A female can lay up to a hundred eggs in a day, and those eggs develop into mature adult flies within 10 to 12 days. A third reason is the simplicity of the fruit fly’s genome, which only has four pairs of chromosomes compared to the 23 in humans. And on a logistical note, the male and female flies are easy to tell apart (genetic studies often require separating males and females, which isn’t an easy feat in all organisms).
“Water bear” or “moss piglet”? No matter what you call them, tardigrades have secured the title of cutest invertebrate—at least in our book. They’re tiny creatures, averaging about the size of a grain of salt, so while you can spot them with the naked eye, using a microscope is the best way to see them. They earned their nickname of water bear and their official name (which comes from tardigradus, Latin for “slow walker”) because of the way they lumber slowly and deliberately on short, stubby legs.
“I’ve always been interested in science and in lizards. I got my first pet lizard when I was around 4 years old, and it was love at first sight,” says Thomas Lozito, Ph.D., who now studies the creatures as an assistant professor of orthopaedic surgery, stem cell biology, and regenerative medicine at the University of Southern California (USC) in Los Angeles.
During his childhood, Dr. Lozito turned his parents’ house into a “little zoo” of lizards and amphibians. He sneaked lizards into his dorm room as a college student at Johns Hopkins University in Baltimore, Maryland, where he earned his bachelor’s degree in biomedical engineering. While pursuing his Ph.D. in stem cell biology through a joint program between the National Institutes of Health and Cambridge University in England, he bred lizards and frogs and sold them to earn extra money.
Scientists often use research organisms to study life. Examples range from simple organisms like bacteria to more complex ones such as mice. NIGMS funds studies of research organisms to understand biological processes that are common to all organisms, including humans. Errors in these fundamental processes can cause disease, and better understanding of these malfunctions can aid in the development of potential treatments.
Research organisms may also reveal novel biological processes that can lead to important scientific or medical technologies. For example, researchers studying interactions between viruses and bacteria made a discovery that led to the CRISPR (clustered regularly interspaced short palindromic repeats) gene-editing system, which was recognized by the 2020 Nobel Prize in chemistry.
As computers have advanced over the past few decades, researchers have been able to work with larger and more complex datasets than ever before. The science of using computers to investigate biological data is called bioinformatics, and it’s helping scientists make important discoveries, such as finding versions of genes that affect a person’s risk for developing various types of cancer. Many scientists believe that almost all biologists will use bioinformatics to some degree in the future.
However, bioinformatics isn’t always included in college biology programs, and many of today’s researchers received their training before bioinformatics was widely taught. To address these gaps, the bioinformatics cores of the five Northeast IDeA Networks of Biomedical Research Excellence (INBREs)—located in Maine, Rhode Island, Delaware, Vermont, and New Hampshire—have worked together to offer basic bioinformatics training to students and researchers. The collaboration started in 2009 with a project where researchers sequenced the genome of a fish called the little skate (Leucoraja erinacea) and used the data to develop trainings.
The tiny roundworm Caenorhabditis elegans is one of the most common research organisms—creatures scientists use to study life. While C. elegans may seem drastically different from humans, it shares many genes and molecular pathways with us. Viewed with a microscope, the worm can also be surprisingly beautiful. Aside from the stunning imagery, these examples from our Image and Video Gallery show how C. elegans helps scientists advance our understanding of living systems and find new ways to improve our health.
Credit: Keir Balla and Emily Troemel, University of California San Diego.
This C. elegans has been infected with microsporidia (purple), parasites closely related to fungi. The yellow shapes are the worm’s gut cells, and the blue dots are nuclei. Some microsporidia can infect people, so studying the parasites in worms could help researchers devise strategies to prevent or treat infections.
Wildlife photos can be truly stunning, and cute cat pictures are a cornerstone of the internet. But zooming in on the early lives of fish, insects, and worms can have equally wonderful results. Using powerful microscopes, researchers are revealing the complexity and beauty of animal development.
Credit: James E. Hayden, The Wistar Institute, Philadelphia, PA.
This image captures the spiral-shaped ovary of an anglerfish in cross section. Once matured, these eggs will be released in a gelatinous, floating mass. For some species of anglerfish, this egg mass can be up to 3 feet long and include nearly 200,000 eggs.
A family of common marmosets. Credit: Francesco Veronesi. CC BY-SA 2.0 .
Fatherhood takes many forms across the animal kingdom. For instance, mammalian fathers are often uninvolved, with only about 10 percent helping to raise their offspring. However, that small percentage of males often makes valuable contributions to their offspring’s upbringing. For instance, cotton-top tamarin and common marmoset dads have the responsibility of carrying babies—which are typically born as sets of twins—almost constantly from birth until independence.
In other groups of animals, fathers are much more likely to share responsibilities with mothers or even act as sole caregivers. Male and female birds contribute equally to raising chicks in most cases. But in rheas and emus—both large, flightless birds—fathers incubate eggs and take care of hatchlings on their own.
And most fish don’t care for their young, but out of the species that do, between one-third and one-half rely on fathers parenting alone. Perhaps the most well-known example is the seahorse, where the male becomes pregnant, carrying his mate’s fertilized eggs in a pouch on his belly until they hatch. Alison M. Bell, Ph.D. , professor of evolution, ecology, and behavior at the University of Illinois at Urbana-Champaign, is investigating paternal care in another fish species where fathers raise offspring solo: the three-spined stickleback. Her work not only helps us understand the value of paternal care for sticklebacks, but also contributes to growing evidence across many species that fatherhood changes males on a physiological level.
Insects vastly outnumber people on our planet. Some are pests, but many are key parts of their ecosystems, and some may even hold secrets for developing new materials that researchers could use in the medical field. Michael Kanost, Ph.D. , a professor of biochemistry and molecular biophysics at Kansas State University in Manhattan, Kansas, has been researching the biochemistry of insects for more than 30 years. His lab studies the tobacco hornworm, a mosquito that carries malaria, and the red flour beetle to better understand insect exoskeletons and immune systems.
Over the past 12 months, we’ve explored a variety of topics in genetics, cell biology, chemistry, and careers in the biomedical sciences. As we ring in the new year, we bring you our top three posts of 2019. If your favorite is missing, let us know what it is in the comments section below!
Hawaiian bobtail squid. Credit: Dr. Satoshi Shibata.
Studying research organisms, such as those featured in this post, teaches us about ourselves. These amazing creatures, which have some traits similar to our own, may hold the key to preventing and treating an array of complex diseases.