The 1500s were a pretty horrible time to get sick. Medicine was kind of a mess. At the time, doctors believed that we were all made of four elements called humors: black bile, yellow bile, blood, and phlegm. Supposedly, when these humors were “imbalanced,” we got sick.

Most of what we knew about human anatomy was from the work of Galen, a renowned Greek philosopher and physician. But Greek and Roman societies prohibited dissection of the human body. So Galen’s knowledge mostly came from dissecting pigs and monkeys, and using their anatomy to guess at the structures inside our bodies, from the muscles to the circulatory system.

It wasn’t until Andreas Vesalius came along that we actually took a good look inside human bodies Vesalius taught medicine and surgery in Italy. And instead of just reading from Galen’s texts, he dissected cadavers for his students, usually the corpses of executed felons. Through those hands-on studies, he discovered just how wrong Galen’s teachings were, and clarified topics ranging from how the circulatory system and nerves worked to bone structure.

For example, Galen believed that the human jaw was made of two bones connected in the middle, from his dissections of dogs. But Vesalius discovered that it’s just one solid bone. After years of research, Vesalius published a set of seven books called De humani corporis fabrica in 1543, which was likely the first complete representation of the human body in the Western world.

Working closely with other artists, Vesalius included over 200 illustrations, from detailed skeletons to networks of blood vessels. As a kinda creepy cherry-on-top, at least one of his books was bound in human skin!

Lots of people consider Vesalius to be the father of modern anatomy. At the very least, his work changed our understanding of the human body, and helped usher Europe into a new, better-informed era of medicine.

Born into a family of German artists and publishers in 1647, Maria Sibylla Merian started illustrating young, painting decorative flowers alongside her stepfather’s male students. At the same time, though, she found herself captivated by insects, especially the life cycle of the silkworm.

So Merian started to collect caterpillars, studying and painting their lifecycle as they metamorphosed into moths and butterflies – along with the plants they ate. In fact, Merian was the first science illustrator to record the relationships between insects and the plants they lived on, which is critical for understanding food chains, as ecologists realized later on.

Plus, she proved that caterpillars hatch from eggs, instead of a common belief that insects randomly appeared from rotting plants and meats. The idea of spontaneous generation dates back to our old friend Aristotle. He never observed insects laying eggs, so he figured larvae just appeared from random places, from old wax to books to horse carcasses.

[exasperated] Aristotle...

Later in life, Merian spent two years traveling with one of her daughters in the Dutch colony of Suriname. Her written accounts were some of the earliest descriptions of the climate, the jungle wildlife, and society in the colony. And in 1705, she published a book called Insects of Suriname, earning her an international reputation as an illustrator. Even today, naturalists use her work as they study and classify insects.

It’s easy to find science illustrators who studied biology, observing plants, animals, and the human body to understand our universe. But Moses Harris was also fascinated by light and color.

Harris was a skilled artist and entomologist, and spent some time studying insects. In fact, he even published a book called The Aurelian in 1766, filled with illustrations of moths and butterflies. When he wasn’t sketching bugs, though, Harris was studying Sir Isaac Newton’s relatively new theories on light.

Newton’s work with light and prisms showed that white light could be split into three primary colors: red, blue, and green. See, light is additive. So cells in your eyes detect different amounts of different colors of light, and blur them together to perceive new colors, even a bright white.

That’s how you’re able to watch this video in color! Right this very second, the pixels on your screen are emitting different combinations of red, green, and blue light.

Harris expanded on color theory to play around with pigments, and demonstrated that yellow, red, and blue are the three primary pigment colors. He also showed that pigments are subtractive color. Basically, they take advantage of how surfaces absorb and reflect different wavelengths of light. A white surface, for instance, reflects all colors of light, while a red surface reflects red wavelengths, and absorbs the rest.

After his experimentation, Harris created an incredible color wheel. Still used by artists today, it shows how mixing any two of the primary pigment colors together generates the secondary colors – orange, purple, and green. While all three together makes black.

Helena and Harriet Scott were born in Sydney in the 1830s, when Australia was still a pretty rough place to be, and women weren’t allowed to study science at university.

Luckily, the girls’ early interest in nature was encouraged by their parents, and when they were teenagers, their family moved to Ash Island, where their dad studied moths and butterflies. The sisters helped their father with his research, cataloging specimens, raising caterpillars to observe their behavior and food preferences, and eventually painting the insects.

Like Maria Sibylla Merian, the Scott sisters depicted the full life cycle of the caterpillars and butterflies they studied. They even included landscape backgrounds of areas in and around Sydney in many of their paintings.

Their dad’s book, Australian Lepidoptera and their Transformations, was published in 1864. And it was so renowned that the sisters were awarded honorary membership in the Entomological Society of New South Wales, and were commissioned to paint for many of the science publications in Sydney. Their skilled work helped document Australian natural history throughout the 19th century, and they were possibly the first female science illustrators in Australia.

Drawings and paintings can be an awesome way to communicate research, but sometimes a 2D illustration just won’t cut it. So some scientific artists branched out into 3D work.

Born in 1822, Leopold Blaschka came from a long line of celebrated glass workers. His day job was creating trinkets and glass eyes for the family business, and training his son Rudolf as his apprentice. In his spare time, he studied plants and flowers, and made delicate glass models which were displayed in museums and botanical gardens around Europe.

During an ocean voyage to the United States, he became fascinated with ocean invertebrates, admiring their glass-like colors and shapes. And in 1863, Blaschka was commissioned by the director of the natural history museum of Dresden to create glass models of sea anemones.

From then on, Blaschka and his son turned all their time and energy to making scientific models. And their work was groundbreaking, artistically and scientifically. While vertebrates like mammals and birds could be taxidermied to resemble living animals, invertebrates could only be preserved in jars.

That kinda worked, but these squishy creatures eventually lost their color and became shapeless blobs. Working first from drawings and later from live specimens kept in saltwater tanks, Blaschka and his son built hundreds of accurate, ethereal glass models of invertebrate sea creatures. Because glass doesn’t need water to survive, these models could be displayed in museums and universities all over the place.

Now, perhaps the most famous collection of their work is the Glass Flowers in the Harvard Museum of Natural History. Over 4,000 models of over 800 species of plants are on display, from entire stalks to magnified pollen grains. And glass flowers are always in bloom!

You’ve probably heard of Peter Rabbit – the cute little bunny in a blue coat who stole carrots from the garden. But long before Beatrix Potter became famous for her stories, she was a wildlife illustrator. As the daughter of a wealthy family, Potter was privately educated, and her scientific interests covered pretty much every field except astronomy. She collected and studied fossils, insects, and even archeological artifacts before finding her true passion: fungi.

The naturalist Charles McIntosh sent her specimens and taught her how to use a microscope, and her scientific skills grew. She was fascinated by fungal reproduction, drawing and painting over 350 illustrations of fungi, down to the details like the gills of mushrooms and their tiny little spores.

Potter successfully germinated mushroom spores in her home. She mounted them on glass slides and tracked their growth, trying to understand how different environments influenced their development. Believing that she was breaking new ground in fungi research, she even wrote a paper called On the Germination of the Spores of the Agaricineae in 1897. Not really sure how to pronounce that one...

Whether or not she really contributed to advancing the field, her illustrations withstood the test of time.

Born in Spain in 1852, Santiago Ramón y Cajal dreamed of being an artist. But, like overbearing parents everywhere, his father pushed him to study medicine instead.

He studied anatomy and pathology, and wrote books and articles about using microscopes to examine tissue samples. But he was struck with passion in 1887, when he learned about a neuroscience lab technique called the Golgi method.

We don’t know exactly how the technique works, but Golgi staining uses potassium dichromate and silver nitrate to fill random neurons with a dark blackish-brown color, and it leaves the tissue around them completely transparent. With this technique, Cajal was able to study individual neurons, which are normally too dense to see under a microscope. Here, he found his calling: illustrating and describing the structure of brain cells.

He made major contributions to the field of neuroanatomy, and helped figure out the basic structure of the brain – a subject of major scientific debate at the time. His sketches proved that neurons aren’t just one long, continuous strand. Instead, he showed the brain was made up of lots of individual, branched cells connecting and communicating with one another.

And he discovered microscopic structures that scientists still study today: like the axonal growth cone, the structure neurons use to guide their growth, and dendritic spines, the little bumps on neurons where they form connections with other cells. Along with the scientist Camillo Golgi, who created the technique, Cajal was awarded the Nobel Prize in Physiology or Medicine in 1906 for his contributions to the field of neuroanatomy.

Many consider him to be the father of modern neuroscience, and neuroscientists today still discuss his drawings of different cells and theories about how they connect and communicate.

Without all these science illustrators, we wouldn’t have the detailed records and models of the natural world that we do today. So no matter how separately they may be taught, science and art are complementary tools to explore and talk about our universe!

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