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Some of my favorite studies in animal anatomy center around coloration. How animals are colored - for example, pigment versus structural coloration - can lead to “next questions” about why they are colored as they are. Two of my recent paintings highlight very different strategies in avian coloration.

The Nicobar pigeon is amazingly flashy. The head and neck are a soft blue-grey with long, tapered feathers, but the rest of the plumage ranges through metallic and iridescent greens, autumn tones, blues and violets. I assumed that Nicobar pigeons would be sexually dichromatic, as is common in birds, but the female’s coloration is only slightly more subdued. Both sexes wear essentially the same spectacular palette.

Nicobar Pigeon, watercolor on paper

The grey morph Eastern Screech Owl I painted represents a very different approach. Rufous, brown and grey morphs are all masters of camouflage. Their false “ears” are actually feather tufts that can be flattened against the head or erected when the bird assumes a vertical pose. Mottled plumage breaks up the owl’s outline, while the dark streaks on its chest can resemble fissures in tree bark.

Screech Owl Grey Morph, watercolor on paper

My assumption was that the different owl color morphs live in different environments or have very different lifestyles, but this proved to be a wonderfully nuanced subject. Researchers have investigated how the frequency of the different morphs changes with climate. In Eastern Screech Owls, the rufous morph is associated with warmer environments, including urban microclimates that are warmer than surrounding areas.

Both species were fun to paint, but both also raised interesting next questions. Why are Nicobar pigeons so flashy if males and females wear a similar color scheme? And research into screech owl color morphs introduced me to Gloger’s rule: the tendency for populations of some warm-blooded animals in warm, humid environments to be more heavily pigmented. Which, naturally, left me wondering: what other animals follow this pattern?

Recently I've been working on a series of gesture studies at Sylvan Heights Bird Park. It's a wonderful place for sketching not only because of its remarkable variety of species, but because visitors can get close enough to notice details that are easy to miss in photographs.

My latest close encounter was with a bird I’d never heard of before, the Abyssinian Ground Hornbill. My first impression was simply its size. Unlike the small hornbills I was familiar with, this species stands nearly a meter tall and spends much of its time on the ground. It is a carnivore adapted to hunting small prey on the open savanna. I can easily imagine what a terror it must be to the insects, small lizards and rodents that share its habitat!

Gesture drawing

As the bird stepped into the sunlight, I was struck by its coloration: black plumage with iridescent blue highlights, contrasting with vivid patches of cobalt blue skin. Males add even more drama with reddish and peach-colored accents on the face and throat.

At close range I could appreciate the textural differences of bill, casque and skin areas, but was most surprised by its lush long eyelashes. I had seen images of ostriches and secretary birds with eyelashes, but something about the hornbill’s contrast between heavy body, strong scaled legs and lethal looking beak combined with unexpectedly glamorous eyelashes was delightfully incongruous.

Gesture drawing

Later research revealed that the "eyelashes" aren't hairs at all, but specialized feather bristles. They likely protect the eyes from the thorny vegetation of African savanna and may help reduce glare from the intense sun.

I decided to make the eyelashes the focus of my painting, choosing a frontal view rather than the more familiar profile that emphasizes the bird's massive bill and distinctive casque. The face-to-face view also reinforces the intense, binocular gaze of a predator.

Final sketch on watercolor paper

I’m preparing for a dinosaur-themed event in late August at the Museum of Life and Science and will definitely be taking my new hornbill painting. Modern birds have become some of our best references for reconstructing dinosaur appearance; cassowaries in particular have been so influential that their bold coloration has almost become a paleoart trope. The Abyssinian Ground Hornbill offers a fresh perspective, and it leads me to a “next question”: if modern birds can surprise us with details like extravagant feather "eyelashes," what other unexpected features might some avian theropods have displayed?

Final painting

For my presentation at the Museum of Life and Science “Bird Bonanza” event, I chose the theme of bird nesting. I’ve done some paintings on this subject over the years and have enjoyed exploring texture effects using modeling paste and glazed colors, as shown in this completed painting.

Snow Goose, acrylic and textural elements on canvas

Detail 

For this year’s event, I wanted to learn more about bird nest construction and materials. I recently read The Hummingbird’s Gift: Wonder, Beauty, and Renewal on Wings by Sy Montgomery, which describes the rescue of hummingbirds and includes some interesting details on nest construction. In addition to other materials, hummingbirds collect spiderweb silk to help create a soft, expandable structure for the eggs and hatchlings. The process is not without risk, as they can become entangled in the web.

I made a trip to the Naturalist Center and found a ruby-throated hummingbird nest. According to the specimen label, it was collected in Wake County in August 2006 after the chicks had fledged. The outside is "shingled" with lichen and the inside is soft fiber.

Ruby-throated hummingbird nest, Naturalist Center

My research always seems to lead me to a “next question”—in this case, why don’t the eggs or hatchlings get wrapped up in the silk? I found that the silk isn’t used in the lining of the nest, which is made of feathers and plant down. Instead, the spiderweb’s elasticity and strength help tie the structural elements of the nest together. By stretching and embedding the fibers among plant down, moss, and lichen, the hummingbird transforms a potentially adhesive material into a soft, flexible, and safe cradle for her chicks. What seemed a risky material choice turns out to be an elegant structural solution!

Ruby-Throated Hummingbird on Nest, watercolor on paper

I’m currently working on similar paintings of an Eastern bluebird and an Eastern screech owl, and am looking forward to discovering what “next questions” arise as I learn more about their nesting habits.

Turtles are wonderful painting subjects, exhibiting many fascinating and sophisticated adaptations, as befits their long lineage. Every time I paint one, I discover a visual feature that invites a deeper look into the “why” behind it.

For the Museum of Life and Science’s Creek Week, I chose two native species: the yellow-bellied slider and the common snapping turtle. For each subject, I created an initial sketch from specimens at the North Carolina Museum of Natural Sciences Naturalist Center. These studies became the foundation for both watercolor paintings and ink versions used as coloring pages for visitors. In developing the educational copy for the coloring pages, I discovered that “sliders” (often seen basking on logs) are named for their habit of sliding quickly into the water when threatened. Somehow, I’d never come across that explanation before.

Yellow-bellied Slider (coloring page)

Comparing the two species raised some interesting questions. One of the first differences I noticed was the snapping turtle’s much longer skull. At first, I assumed this might simply provide additional space for muscle attachment, but the reality is more nuanced. As a predator, the snapping turtle benefits from a long, wedge-shaped skull that increases strike reach, accommodates powerful jaw musculature, and helps channel the stresses of a forceful bite. In contrast, the slider’s skull is adapted for less forceful feeding, such as cropping vegetation.

Sketch of Common Snapping Turtle Skull and Lower Jaw

The second point of interest was that the eye coloration pattern differs noticeably. Turtle eyes vary widely in appearance. Some, like sea turtles, have eyes that appear almost gentle—and even eerily human. In my Creek Week subjects, the slider has a horizontal bar of darker color across the iris, while the snapping turtle’s eye includes both horizontal and vertical bars, creating a “crosshair” effect.

Detail of Yellow-bellied Slider and Snapping Turtle paintings

There are several hypotheses behind these patterns, and two in particular stood out to me.

One idea is that the snapping turtle’s “crosshairs” function as disruptive coloration, helping to obscure the eye and making it harder for prey to detect exactly where the turtle is looking. Predators such as tigers show somewhat similar strategies, with facial striping that breaks up the outline of the eyes and even “eyespots” on the backs of their ears.

Another hypothesis is that horizontal bars—seen in both species—may help reduce glare from the water’s surface and enhance contrast along the horizon. Interestingly, grazing mammals like horses and goats achieve a similar visual effect through horizontally elongated pupils, suggesting a comparable functional goal reached through a different anatomical solution.

I’m looking forward to exploring turtle morphology further—there always seems to be another layer of structure and function waiting just beneath the surface.

Snapping Turtle, watercolor