Creature Feature
Fowler’s Toad (Bufo [Anaxyrus] fowleri)
by Jeff Beane
Childhood is a toad in the garden, a happy toad.
–William Carlos Williams
For naturalists in the North Carolina Piedmont, April is a pretty fine month. Spring is in full swing, filled with the sights and sounds of many things happening at once. If you live near almost any sort of pond or wetland, a harsh, nasal “waaaaah!” will be just one of the sounds you can welcome at this time each year. It means another breeding season is beginning for Fowler’s Toad (Bufo [Anaxyrus] fowleri).
The word “toad” has no precise scientific definition—it’s a general term used for anurans that tend to have chunky bodies and dry, warty skins; that hop rather than leap; and that are encountered more often on land than around water. There are actually many families of anurans (Anura, literally meaning “tailless,” is the amphibian order that includes all frogs and toads), and many of them contain members commonly called toads. The toads that most folks are most familiar with belong to the large family Bufonidae—the “true toads.” Fowler’s toad is the most widespread, and perhaps the most frequently encountered, of North Carolina’s four bufonids. It ranges throughout the Piedmont, much of the northern and inner Coastal Plain, and lower elevations in the Mountains. The American Toad (B. [A.] americanus), is more common in the Mountains, but also ranges throughout most of the Piedmont and the northern Coastal Plain. The Southern Toad (B. [A.] terrestris) occurs throughout most of the Coastal Plain. The tiny Oak Toad (B. [A.] quercicus) is also a resident of the Coastal Plain, where it has undergone sharp declines in recent years.
Recent genetic work on bufonids has prompted some systematists to “split” the once-huge genus Bufo into several genera, and North Carolina’s four species have been recently assigned to the genus Anaxyrus. But taxonomy is a controversial science, with much subjectivity involved, and published changes are not always immediately or unanimously accepted. It will be a long time before some of us old-timers stop using names we’ve known our entire lives. As my friend Dave Stephan put it: “I will stop using the names Rana [a common frog genus] and Bufo when they are pried from my cold, dead hands.”
Bufo is Latin for “toad.” Anaxyrus is from the Greek ????, meaning “sovereign” or “king.” The species name honors Samuel Page Fowler (1799-1844), New Jersey statesman, member of U.S. House of Representatives, and mineralogist (the mineral Fowlerite is also named for him). Fowler’s toad was until fairly recently regarded as a subspecies of the Woodhouse Toad, B. [A.] woodhousii. The two are now recognized as separate species.
Fowler’s Toad is easily and often confused with the American Toad and Southern Toad—the three are similar in appearance and occasionally hybridize where their ranges overlap. Usually no more than two of the three occur together in any one locality. Around the greater Raleigh area, we have Fowler’s and American toads, with Fowler’s being slightly more common (see chart below for ways to distinguish these two). Southern toads may enter extreme southern Wake County.
Toads are strictly carnivorous, and will feed on almost anything small enough to catch and swallow. Prey items must be swallowed whole; toads are not capable of chewing or biting off chunks. Small prey are snapped up with a quick flick of the toad’s sticky tongue. A toad may use its forelimbs to help shove larger items down its throat. The great majority of the diet is insects, but toads will also eat other arthropods, worms, and small vertebrates; the only things they don’t manage to get down are those packing a very powerful wallop via stings, bites, or harsh chemical defenses—and even some of these may elicit repeated attempts at being swallowed before the toad gives up. They have strong stomachs and manage to eat some fairly noxious prey items. Virtually all farmers and gardeners know of toads’ well-deserved reputations as insect control agents and welcome them in yard, field, and garden. Toads may be active day and night, but are more often nocturnal, especially in hot weather. They may gather at outdoor lights at night to eat the insects that accumulate there. Such “porch light toads” often become tame, and many a child has made a game of tossing insects to a backyard toad. Toads detect prey visually, by motion, and will attempt to feed on virtually any small moving object. A toad surrounded by fresh dead insects would starve—they are not noted for their intellect.
Toads and other amphibians absorb water through their porous skin; they do not “drink” in the same fashion as do most mammals, birds, and reptiles. A Fowler’s Toad’s skin is thicker and drier than that of many amphibians, allowing it to live its entire adult life on land. Toads must remain at least somewhat cool and moist, however, and will seek underground refugia in hot or dry weather. They also spend the colder months belowground. A toad breathes mostly through its lungs, but some oxygen exchange also takes place through its skin.
Like a great many amphibians, toads produce skin secretions that make them unpalatable or even toxic to many predators. Nonetheless, they are eaten by many animals whose stomachs can neutralize the toxins. The Eastern Hognose Snake specializes on toads, eating very little else, and some other snakes, including garter snakes and Red-bellied Water Snakes, can eat toads with impunity. Snapping Turtles also eat them. Raccoons, skunks, crows, and some other predators may eviscerate toads, eating only the nutritious liver and other internal organs and leaving most of the carcass. Newly transformed toads, besides being smaller, have milder toxins; they have many more predators than do adults. Birds such as grackles and jays have been observed eating large numbers of toad metamorphs. The biggest threats by far, however, are humans with their vehicles, mowers, domestic animals, and pesticides. But even the killing of huge numbers of individual toads by these factors pales in comparison to outright loss and fragmentation of habitat. Still, the adaptable Fowler’s Toad manages to survive in some suburban and semi-urban areas, as long as there is a place to breed and some terrestrial habitat. Its adaptability has allowed it to remain common in the face of serious declines among other amphibian species.
Like all of North Carolina’s anurans, Fowler’s toads must breed in water. They utilize a great variety of wetlands for breeding, from puddles to lakes and rivers. They readily use permanent water, and the construction of farm ponds, reservoirs, and other artificial bodies of water has probably greatly benefited them. Their tadpoles, unlike those of many amphibians, are tolerant of fish; they avoid them by staying mostly in very shallow water, by hiding in vegetation or bottom litter, and by being bad-tasting.
In the Raleigh area, Fowler’s Toads usually begin calling around the first week of April, but that varies with temperature, water levels, and location. The breeding season is prolonged, often lasting until July or August. Males call to attract females and to maintain territories (females are silent). They may sit in shallow water or on land when calling. Sound is produced by inflating the vocal sac and forcing air across its thin membrane. Different frog and toad species have different types and shapes of vocal sacs. A Fowler’s Toad has a single, spherical one that inflates like a balloon under his throat. The call has been compared to the bleat of a sheep. When a female approaches, a male grabs her and clasps her tightly just behind the armpits with his forelimbs. This position is called amplexus. He will hold onto her until she releases her eggs and will dump sperm on the eggs as they are laid. Enthusiastic males may try to mate with other males, or with other amplexed pairs. In extreme situations, males may form mating balls with a female or two somewhere in the middle; on rare occasion females, or even males, may be overwhelmed and drowned. Males emit a chirping “release call” when clasped by another male. The particular frequency of this call usually causes a male to realize his mistake and release his would-be mate. Male toads will also utter this release call when handled, and this is a useful method of distinguishing the sexes; another is that males have dark throats while those of females are plain white. Females also attain slightly larger sizes than males.
Fowler’s Toads deposit their eggs in long strings. Two strings are produced simultaneously—one from each ovary—totaling around 7,000 eggs. They are randomly strung in vegetation or on the shallow pond bottom. The eggs hatch in about a week and the small, black tadpoles grow quickly, feeding mostly on algae and other organic material, which they scrape from the substrate with the keratinized rows of teeth lining their small mouths. They transform in about one to two months at small sizes—newly transformed toads are only about 0.3-0.4” (8-11 mm) long. They can be found leaving ponds in huge numbers. They may disperse far from the wetlands, and will immediately begin eating insects and growing rapidly. Some may reach sexual maturity in as little as a year, while others require two or three years. They will live the rest of their lives on land, except for returning to ponds or wetlands annually to breed. Only a tiny percentage of the thousands of eggs laid by a female toad will end up as breeding adults.
For defense, toads rely on cryptic behavior (hiding, camouflage), on flight (hopping quickly away toward cover); and on their skin toxins. Rough handling can result in a toad exuding its milky-white toxins—called bufotoxins. These are produced in various places in the toad’s glandular skin, but especially in the two large, oval glands located on each side of the head—the parotoid glands. Bufotoxins may have hallucinogenic properties in small quantities. Some species of toads—most often the Sonoran Desert Toad (Bufo [Incilius] alvarius) and the Marine Toad, or Cane Toad (B. marinus [Rhinella marina])—are actually abused as a drug; live toads are licked, or their skins are dried and eaten or smoked. Some Native American tribes are known to have dried toad skins and smoked them ceremonially. Such activities can, of course, potentially result in severe vomiting, brain damage, or death. North Carolina’s toads have relatively mild toxins and are more likely to induce instant vomiting in a human than either hallucinations or death. They are harmless to human skin, but can cause severe irritation if rubbed in the eyes or other mucous membranes. In other words, toads may be safely handled, but don’t eat or lick them, or rub your face or any other sensitive part of your body with them. Needless to say, they do not cause warts.
A frightened toad will also inflate its body with air to make it larger and harder to swallow, and will release excess water (this is not urine, as is commonly believed) from its cloaca. Toads may also feign death when handled. This might seem like self-defeating behavior, but a toad that is swallowed by a snake without a struggle sustains no injuries, and just might survive if the snake happens to regurgitate it later because of its skin toxins or for some reason.
Potential longevity is poorly known for most toad species, but some bufonids have lived for longer than 20 years in captivity. It seems reasonable that a Fowler’s Toad could live for 10 years or more in the wild if it could escape predators for that long (very few do).
Watch for Fowler’s Toad in your yard or garden this spring, and listen for its harsh-but-friendly voice on spring and summer nights. As neighbors go, you could certainly do worse.
Fowler’s Toad American Toad
| Most dark spots on back will each contain 3 or more warts. | Most dark spots on back will each contain 1 or 2 warts. |
| Cranial crests (bony ridges on top of the head behind each eye) are small and inconspicuous. Parotoid gland (large, oblong gland on each side of the head) is usually flush against cranial crest. | Cranial crests are well-developed and conspicuous. Parotoid gland is usually separate from cranial crest or connected by a short spur. |
| Smallish warts on outer surface of tibia or shank of hind leg. | Enlarged warts on outer surface of tibia or shank of hind leg. |
| Underside usually plain white with a single dark spot on chest/throat. | Chest often mottled with dark pigment; usually no single dark spot. |
| Smaller; maximum snout-vent length about 3.25” (82 mm). | Grows larger; maximum snout-vent length about 4.25” (107 mm). Largest specimens are from Mountains. |
| Snout slightly more pointed. | Snout slightly more broadly rounded. |
| Color highly variable, but sometimes greenish. | Color highly variable, but usually brown, gray, or reddish; seldom looks greenish. |
| In Raleigh area, usually calls from early April to August. | In Raleigh area, usually calls from late February to April. |
| Call is a harsh, nasal “waaah,” ca. 1-4 seconds in duration. | Call is a long, musical, whistlelike trill, ca. 20-30 seconds in duration. |
| Breeds in a wide variety of wetlands, but often prefers farm ponds, lakes, or other permanent water. | May use permanent water, but prefers woodland pools or other temporary wetlands. |
| Tends to have slightly lower, more horizontal posture and slightly smaller forelimbs. | Tends to sit more upright; forelimbs slightly larger. |
| Usually a distinct whitish mid-dorsal stripe. | Mid-dorsal stripe often present, but not always distinct; sometimes faint or absent. |
Every year, at some point between mid-April and mid-May, a few Wake Audubon members go wild. This is a result of the Wildathon—our version of National Audubon’s Birdathon. The event embodies what you’d expect from any sort of “-athon”—it’s an exercise in endurance. The purpose: To identify as many species as possible in a given time period, to raise money for various wildlife conservation projects, and to have fun and learn. Individuals or teams seek sponsors who pledge either a per-species amount or a flat donation. Wake Audubon doesn’t limit its efforts to birds—teams may count any species they choose, and may make and modify some of their own rules, as long as the rules are clear to the sponsors.
Wake Audubon began participating in this event in 2000. Every year since then, I and at least a few others have looked forward to this special day. Over the years, my team has included various combinations of David Cooper, Ed Corey, Bob Davis, John Finnegan, Stephanie Horton, Todd Pusser, and me. We’ve most often had four team members—sometimes as few as three or as many as five—more than that is too many for this type of event. We all have to get along well together for an entire day and night at full throttle. Some years we’ve had team members drop out or take a break after a long stretch, and we’ve been known to bring in subs from “off the bench.” Our first year’s effort lasted just 18 hours, but every year since then we’ve done a full 24, which isn’t as easy as it sounds. Just staying awake for 24 hours can be sufficiently difficult, but remaining intensely active, both mentally and physically, for that long, doing everything within reason to turn up just one more species before the time runs out (and it does go by mighty fast) is a real challenge—one we embrace each year. We named our team the “24-Hour Dream Team.” The “dream” part refers not to any illusions of greatness, but more to the late stages of the event, during which our exhaustion can bring on a certain dreamlike state that seems almost surreal. Usually our 24 hours extend over two different dates—i.e., we usually start early in the morning and end at the same time the next morning, although some years we have gone from midnight to midnight. Davis, Finnegan, Horton, and I formed the original Dream Team, sometimes joined by Pusser. In 2007, Ed Corey formed a team that also followed our 24-hour rules. Some years we have combined forces, and other years we’ve run separate teams. This year, our team will consist of Ed Corey, Bob Davis, John Finnegan, Stephanie Horton, and me. We will “run” our event over 5-6 May, beginning Saturday morning and ending Sunday morning. We plan to start at Carolina Beach and will probably end in the Sandhills, somewhere near Hoffman. Friday afternoon, we’ll head down to Carolina Beach, and will sleep in Bob Davis’ beach house that night. After time runs out Sunday morning we will retire to my Sandhills house near Hoffman for a few hours of recoverative sleep before heading back to Raleigh that afternoon.
Our team counts vertebrates (fishes, amphibians, reptiles, birds, and mammals), primarily because we can reasonably identify most species in that group. We count every live or dead species that we can identify by sight or sound in 24 hours, anywhere in North Carolina. We count only wild, free-ranging native species or well-established exotics (e.g., House Sparrow, Red Fox, Rainbow Trout). We do not count domestic animals (like dogs, horses, or chickens) or captives (like parrots, aquarium fishes, etc.). Not every team member need see or hear a species for it to be counted, but identifications must be accepted by the entire team. Many other teams count only birds, but some may choose to count butterflies, plants, etc.—whatever the team chooses and is comfortable with. So far, we have limited our efforts to North Carolina, and have focused on the southeastern Coastal Plain and Sandhills regions, where the highest vertebrate diversity is to be found. Of our 12 Wildathons to date, our highest total was 217 vertebrate species, in 2011. Our lowest was 155, but that was our first year (2000), when we only spent 18 hours.
Wildathon proceeds support NC Audubon’s Coastal Island Sanctuaries, local chapter projects, and two conservation and research initiatives of the North Carolina Herpetological Society (Project Bog Turtle and Project Simus, aimed at the Bog Turtle and Southern Hognose Snake, respectively, and their habitats). During these difficult economic times, we must work harder than ever to raise funds for these excellent causes.
And that’s where you come in. You can support the Wildathon by forming a team, or by counting birds or other species on your own, in whatever fashion you choose, and soliciting your own sponsors. Or, if marathon counts aren’t among your strong points, perhaps you will consider sponsoring or donating to one of our existing teams—those of us who go wild each year in support of Wake Audubon, and of the wild creatures and wild places we love.
To donate, to form your own team, or to receive more information, contact Jeff Beane ([email protected]), Ed Corey ([email protected]), John Gerwin ([email protected]), or Gerry Luginbuhl ([email protected]).
— Jeff Beane
One of my favorite spring wildflowers is the Little Brown Jug, or Arrow-leaved Heartleaf (Hexastylis arifolia). It’s also one of the most common wildflowers in the Raleigh area. You’ll see them growing in deciduous and mixed woodlands over much of Wake County and the surrounding area. What you generally see are the leaves, which are triangular in shape and somewhat fleshy, nestled in the leaf litter on the forest floor. For most of the year, the leaves have distinctive pale patches between the major veins. This time of year, when the new leaves are unfurling, you’ll see the pale blotches only on last year’s leaves. It takes a while before the new leaves develop their mature coloring. The leaf blades are two or three inches long, with a leafstalk that’s usually about six or eight inches long. The leafstalks lop down on the ground.
What you don’t usually see are the flowers, but they’re blooming this month. If you bend down, brush the fallen tree leaves away, and follow the leafstalks to the base of the Little Brown Jug plant, you’ll see the jugs, the flowers that give the plant its name: brown, vase-shaped, and about an inch long, with three pointed lobes at the mouth of each jug. Within those jugs, some of the most interesting facts about the plant’s life reside. The whole plant has a gingery odor, and this odor attracts fungus gnats, which crawl inside the flowers and pollinate them. Although the plants are self-fertile, they still need the gnats to transport the pollen from the anthers to the stigmas. After about a month and a half, seeds develop at the base of the jug. Each jug produces, on average, about twenty seeds, and each seed is about eight tenths of a millimeter long, hardly longer than a poppy seed. However, the plant now needs help from a different insect: ants. Like many forest wildflowers, the Little Brown Jug uses ants to disperse its seeds, and to entice the ants it produces a small, fat-rich appendage on each seed. The ants carry the seeds off, eat the appendages, and leave the rest of the seed near their nest.
The first year after the seeds sprout, only the cotyledons appear. During the second year a single leaf grows. It may take seven or eight years before a plant is ready to bloom. The plants are fully perennial, though, and can live for up to twenty years. Watch for them the next time you stroll through a forest here in the Triangle, and bend down to see if you can find the jugs.
Erik Thomas, Wake Audubon Board Member
It is hard to believe, living in Raleigh, NC, that when I was growing up the first time I saw a bluebird was as a college student in upstate NY, and what a thrill it was! What a joy to see the beautiful bright colors of what at the time, was a rare bird, and actually is the state bird of New York.
From the 1940’s until the 1970’s, bluebird populations were in decline, due to competition for nest sites from non-native house sparrows and starlings, as well as the use of DDT. Habitat loss increased as well, and outdoor cats were and continue to be a threat to bluebirds as well as other species. However, with the discontinuation of DDT spraying, and the establishment of bluebird trails and increasing use of nestboxes by individuals around the country, the beautiful birds have made a comeback.
If you are interested in seeing some unique birdhouses for bluebirds and other birds, be sure to come out to the 12th Annual Birdhouse Competition on Saturday and Sunday April 14-15 at the JC Raulston Arboretum in Raleigh.
Beth Gaffer, Wake Audubon Board Member
Eastern Bluebird Nest - Jeff Beane
24-hour Grand Opening of the North Carolina Museum of Natural Sciences Nature Research Center
Volunteers are needed to staff the Wake Audubon Society booth for the opening of the Nature Research Center, which is being held on April 20-21. The booth will focus on the chimney swift fundraising/education efforts. This booth will have both educational elements (faux chimney that opens up to show you a swift at a nest) as well as a fun game or two (chimney swift bean bag toss into a chimney, like the corn-hole game everyone is playing these days). We will have prizes, an educational activity packet designed by Annie Runyan for sale, etc. WAS will have a booth on Saturday, April 21 from 8 am-6 pm. The Museum expects 100,000 visitors at the NRC opening.
Prior to the event, WAS needs help on this event committee.
If you would like to help with the event and/or serve on the event committee, please contact Anita Kuehne at [email protected]
The new 80,000 square-foot wing of the North Carolina Museum of Natural Sciences will connect people to research by bringing scientists and their work into the public eye, helping demystify what can be an intimidating field of study, better prepare science educators and students, and inspire a new generation of young scientists.
The mission of the NRC is “Connecting People to Research.”
Early in August, my husband and I traveled to the old family homestead, which is located deep in the mountains of western Pennsylvania. It is a lovely getaway, with active trains passing by at different times of the day. We do a lot of birding up there during our stays and have seen some life birds there too. The “Big Deal” every morning/evening while you are there, is to go outside and wave at the passengers of the Amtrak coaches.
One morning, while drinking my cup of espresso on the front porch, we noticed these beautiful butterflies flying/landing on the railing. They were black/blue and marked very prettily. We watched them for over an hour and my husband took their picture. I have guessed that they were Dark Swallowtails. Then during lunchtime we noticed this other odd looking thing on the plants which I have been told was a Butterfly Moth. Again, my husband took its picture. Then during the afternoon, as we exit the stonecutter’s sales shop, my husband spotted this female Killdeer on a nest in his front yard. We did not want to disturb her but she surely made us aware she was not happy with him taking her picture!
Since that day, I now search for large & small butterflies everywhere we go. My new butterflies field guide is always with my birding guide. While outdoors enjoying nature, it is now more fun for us, with or without birds present. Guess I’ve been a little slow to catch on with butterflies, but I have added them to my birding walks. “You are never too old to learn something new and have fun at it”. Oh, Oh! I just saw a dragonfly!!!
Angie DeLozier
It is an unfortunate consequence of human’s dominion over nature that sometimes wildlife is harmed. Luckily for us, we have some local resources that can help injured wildlife. It seems like I am always coming across some poor bird or other critter that is in obvious distress.
NC State Vet School’s Turtle Team will accept all injured herps (reptiles and amphibians). They are wonderful! They even let you release the animal back where you found it once it is healed. I once found a box turtle at Anderson Point Park (our Adopt-A-Park) with an aural swelling. I was leading a bird walk at the time-I am sure the participants thought I was crazy! I brought him to Turtle Hospital (at the NCSU Vet School Animal Emergency Clinic) and hoped he would be OK. Months later I get a call that he’s ready to go home! It was such a delight to pick him up and bring him back to Anderson Point Park. I watched as he wandered off towards the point and wished him luck.
Once I hit a toad with my bicycle and injured his eye. I brought him to the Turtle Team and time faded away. About a year later I get another call. Unbelievable, Genghis Toad was ready to go home. I’m not sure why he got that particular moniker (he was a small toad) but I thought it was pretty cute that he had been named. He had been living and recuperating with one of the vet students. He was blind in the injured eye but was a good eater so it was time to come home. I let him go in my backyard, just a short distance from where his injury had taken place.
Other animals can be taken to Triangle Wildlife Rehabilitation Center. I have brought them birds and bunnies. They will accept all native wildlife. They will also allow you to release the animal back where it was found which is vital for the animal’s success.
Some tips if you find an injured animal:
-Be very careful handling injured wildlife. You do not want to get bit!
-Do not offer food or water.
-Keep animal in a ventilated cardboard box in a warm, dark, quiet area away from children and pets.
-Please support the institution with a donation. I read once that it costs, on average, $40 to rehabilitate an injured animal, so I always write a check for $40 with each animal I bring to a rehabber.
One other very important thing to keep in mind is that many of the animals that are brought in to these clinics are injured by cats!! Please do your part to keep wildlife (and cats!) safe; keep your cat indoors!
Contact information:
NCSU Turtle Team: 919-513-6500
Triangle Wildlife: 919-544-3330
Thanks for doing your part to keep our wild animals safe and happy!—Kari Wouk, WAS Board Member
By Sean Higgins, Wake Audubon Board member
In April, 15 teens joined the Mysterious Carolina Bay Lakes excursion cosponsored by the Wake Audubon Young Naturalists and the Museum of Natural Sciences Junior Curators. Many people generously contributed resources, time and energy to make this a Spring Break to remember for these youth.
Lynn Cross has an absolutely amazing rapport with high school students (not to mention her expertise in the art of smores)! Big props to staff at Singletary Lake State Park and Lake Waccamaw State Park. Staff of both went way out of their way to accommodate our group and make us feel quite welcome… despite both parks having major events on the same days including a county-wide Environmental Field Day at Lake Waccamaw. Ranger Lane Garner gave a great overview of “What is a Carolina Bay?”, Superintendent Chris Helms guided us in a freshwater mussel survey, and I&E Specialist Brittany Whitaker guided night activities. We even had an impromptu live alligator program onboard the bus when N.C. Museum of Forestry educator Kellie Lewis flagged us down on the side of the road.
Who knows where Spring Break 2012 could take these groups? Bear Island? A river trip? Or will the groups brave the unpredictable spring weather in the mountains?
You are receiving this email because you play a valuable role in these programs, perhaps behind the scenes. Cheers to a new generation of conservationists!
Canoeing at Singletary Lake. With the fierce wind, we made it all the way around the lake in about 2 1/2 hours. Next time we’ll bring a catamaran.
Collecting and observing aquatic critters as the sun sets on Singletary Lake. You can almost hear the voice of Otis Redding through the trees.
Add Tidewater Fatmucket to your life list!
Don’t pick up hitchhikers… especially the crocodilian kind.
Log… log… log… whoa, there’s a gator!
by Nathan Swick, Wake Audubon Board member
A talk that may be of interest to birders in the area is coming to the Museum of Natural Sciences. Legendary evolutionary biologists Peter and Rosemary Grant present highlights of their life’s work on in a free program in the auditorium at 7 pm on April 11.
Peter Grant is professor emeritus of zoology, and Rosemary Grant is a retired senior research scholar, both in the Department of Ecology and Evolutionary Biology at Princeton. In their dogged study of a population of birds popularly known as “Darwin’s finches,” the Grants have won renown for detecting and recording evolution in action, and proving and extending the theories of pioneering evolutionist Charles Darwin, work for which they were recently awarded the prestigious Kyoto Prize.
For much of the public, the work of the Grants first came to light in Jonathan Weiner’s Pulitzer Prize-winning account of their efforts, “The Beak of the Finch.” Published in 1994, the book detailed the couple’s arduous, yearly six-month stay in tents on Daphne Major, a desolate volcanic island 600 miles west of Ecuador. There, since 1973, they have undertaken what was described in Weiner’s book as one of the most intensive and valuable animal studies ever conducted in the wild.
“We choose a single group of related species for close scrutiny,” the Grants wrote, “and attempt to answer the following questions: Where did they come from, how did they diversify, what caused them to diversify as much as they did (and no more) and over what period of time did this happen?” What the Grants have shown through their relentless study and cataloging of 14 varieties of island finches is how beak size and shape evolve through natural selection within a dramatically changing environment, according to certain mechanisms and conditions.
This presentation is made possible through a partnership between the Museum, North Carolina State University’s WM Keck Center for Behavioral Biology, and the National Evolutionary Synthesis Center (NESCent).