Melbourne Bone Bed Fossils — Melbourne, Florida

The Melbourne Bone Bed is a layer of Ice Age fossils under the west side of Melbourne, logged by the University of Florida as Vertebrate Fossil Locality BR002. The Florida Museum of Natural History places it in the western part of the city at about 28.1 degrees north and dates it to the late Pleistocene, the Rancholabrean land mammal age, at roughly 11,000 to 25,000 years old. It ranks Melbourne among the Big Three late Pleistocene sites found in Florida during the first half of the 20th century, alongside the Vero Canal Site in Indian River County and Seminole Field in Pinellas County.

Most museum specimens came from two digs along Crane Creek. The Golf Course locality sat on the east bank of the creek where it crossed the Melbourne Golf and Country Club, south of West New Haven Avenue, and stretched at least 100 feet with an average width of 30 feet. The Singleton Estate locality, then an orange grove, lay about a mile to the south-southwest, and a third, thinner site was on the south bank of the straightened channel roughly a mile west of the golf course.

The age comes from the animals themselves. The Florida Museum explains that the mix of species at Melbourne, including the hispid cotton rat, the marsh rice rat, the dire wolf, the Florida spectacled bear, the puma and the glyptodont Glyptotherium floridanum, points to the late part of the Rancholabrean, a method called biochronology. A second check is the stacking of the beds: the bone layer sits above a shelly unit generally equated with the Anastasia Formation, laid down in the last major interglacial about 125,000 years ago, so every bone above it must be younger.

Scientists of the 1920s and 1930s numbered the layers along Crane Creek. Bed 1 is the shelly sand at the base. Bed 2, the fossil horizon, is a 4- to 5-foot band of fine brown sand whose top is an uneven erosion surface. Bed 3, on top, alternates sand with decomposed plant matter that James Gidley in 1929 interpreted as a swamp deposit. Most researchers read Bed 2 as stream channel and flood sediment, though Gidley proposed that it was wind-blown sand. The museum notes that no sediment was screenwashed in those years, yet the many tiny rodent fossils from Melbourne show the diggers worked slowly.

The Florida Museum faunal list for Melbourne reads like a roster of vanished giants. Proboscideans are represented by both the American mastodon and the Columbian mammoth, Mammuthus columbi. Ground sloths include Megalonyx jeffersoni and Paramylodon harlani, and the armored mammals include the glyptodont, the pampathere Holmesina septentrionalis and the beautiful armadillo, Dasypus bellus. The Florida Museum species page for Dasypus bellus describes it as about two to two and a half times the size of the living nine-banded armadillo, and lists Melbourne among its Brevard County sites.

Hoofed animals filled out the grasslands and woods along old Crane Creek: an extinct horse, Equus fraternus, a tapir, two kinds of extinct peccary, two extinct llamas, bison and white-tailed deer. Two oversized rodents stand out, the giant beaver Castoroides dilophidus and the extinct capybara Neochoerus pinckneyi. The museum observes that browsers such as deer, tapir and mastodon and grazers such as horse, bison and mammoth were about equally common at Melbourne, a large mammal mix very similar to Seminole Field, while the ground sloth Megalonyx turns up more often at Melbourne. James Gidley's tally through the 1926 field season counted 36 species of mammals other than humans, 7 reptiles, one fish and 4 birds, though many of his names were provisional and later revised.

Melbourne has an unusually long list of carnivores. One species was named from it: the Florida spectacled bear, Tremarctos floridanus. According to the Florida Museum, the type locality of the species is the Golf Course locality in Melbourne, and its holotype, the specimen that defines the species, is a partial skull and jaws from the site. Gidley first placed it in the genus Arctodus in 1928 before it was moved to Tremarctos. The museum describes the bear as much more common as a fossil in Florida than the living black bear and thought to be primarily a herbivore, like the spectacled bear of South America.

Big cats came in three kinds. The Smilodon fatalis page lists Melbourne among Brevard County sites for the saber-tooth cat and gives it a body mass of 350 to 600 pounds, close to a Siberian tiger. Jaguar fossils from Melbourne were described and figured by George Gaylord Simpson in 1941, and the Panthera onca page notes that Pleistocene jaguars of North America were much larger than those living today in Central and South America. A puma and a bobcat also appear on the site list.

Dogs were well represented too. The Canis dirus page records the dire wolf at Melbourne and estimates its mass at 130 to 150 pounds, about 25 percent heavier than a modern gray wolf. A wolf jaw from Melbourne studied in 1958 was later identified as a red wolf, Canis rufus, and coyote, gray fox, red fox, skunks, a raccoon and a river otter round out the Melbourne carnivores, according to the Florida Museum.

The bed preserved far more than big mammals. Reptiles include an extinct snapping turtle, Chelydra osceola, the extinct box turtle Terrapene putnami, the extinct giant tortoise Hesperotestudo crassiscutata, the gopher tortoise, the eastern indigo snake, the cottonmouth, the eastern diamondback rattlesnake and the American alligator. Charles Gilmore described a new species of large box turtle from Melbourne in 1927, and a gar is the lone fish.

Birds studied by Alexander Wetmore in 1931 include wild turkey, Canada goose, anhinga, great blue heron, whooping crane, sandhill crane, bald eagle, osprey and crested caracara. The most striking is an extinct stork. The Ciconia maltha page credits Wetmore with recording it at Melbourne and describes a bird over 4 feet tall with a wingspan up to 9 feet. A single toe bone of the Caribbean monk seal also came from the site, though the Florida Museum notes it may derive from the older shell bed beneath.

Small mammals include the round-tailed muskrat, cotton rats, rice rats, rabbits, a mole and a shrew. The best-known small fossil is a jaw of a large bat, named Molossides floridanus in 1932. Later study placed it in the bonneted bat genus Eumops, and in 2004 it was raised again to a full species, Eumops floridanus, that includes a rare living population in southernmost Florida, one of few cases since 1900 of a species named from fossils and later found to be living. The U.S. Fish and Wildlife Service describes Florida bonneted bats as endemic to south Florida, from south of Orlando to Miami, with wingspans of up to 20 inches.

No single museum holds the Melbourne collection. The Florida Museum records that C. P. Singleton, who found and reported the fossils to the Smithsonian Institution in 1922, divided much of his early material between the Smithsonian and Amherst College in 1925, and that the bones he dug at the Golf Course locality from 1925 to at least 1928, apparently with Harvard funding, went to Harvard's Museum of Comparative Zoology. A Columbian mammoth collected at Melbourne by Frederick Loomis and Singleton stands mounted at the Beneski Museum of Natural History at Amherst, very likely the first mounted skeleton of a Florida fossil placed on public display.

That split, and Gidley's death in 1931, left the Melbourne animals understudied. The Florida Museum counts relatively few detailed papers on the non-human fossils given how large and well preserved the samples are, and it suggests that many comparable sites likely lie undiscovered beneath Florida's developed coast. The human remains found in the same Crane Creek digs, and the scientific dispute over their age, are covered on the separate Melbourne Man page.