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The Curious Incident of the Non-Rafting Foxes

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Blink and you might miss this unexpected bit of common sense, embedded in a NY Times article on adorable dwarf foxes native to California’s Channel Islands (“Foxes That Endure Despite a Lack of Genetic Diversity“). How did they get there? They were evidently ferried thousands of years ago by Native Americans, who seemed to regard them as totem animals.

It’s unlikely the foxes made the trip on their own; the islands are separated from the mainland by 12 to 70 miles of open ocean. Another clue pointing to human help: Native Americans painted foxes on rocks and gave them ceremonial burials. Foxes may have had a spiritual importance to them.

However the animals arrived on the Channel Islands, they adapted quickly. The oldest island fox fossils date back 7,000 years and show that they were small even then. [Emphasis added.]

Fine. Because otherwise how else could a fox make the passage? Just imagine: foxes rafting across 12 miles of ocean on their own, never mind 70 miles — perhaps hitching a ride on a tree trunk or other matted vegetation torn from the ground in a violent storm. It’s like something out of a kids’ cartoon. That indeed sounds pretty “unlikely.” Actually, “absurd” is more like it.

Now would you believe unaided animals journeying across ocean waters not for 12 or 70 but hundred of miles? Because the journal Nature tells us monkeys did it. From the Washington Post:

Ancient primates may have traveled from South America to North America about 21 million years ago — back when the continents were separated by 100 miles of water. The swashbuckling monkeys are reported in a study published Wednesday in Nature magazine.

“We never would’ve predicted they would’ve been here,” lead author Jonathan Bloch of the Florida Museum of Natural History told Nature.

Bloch and his colleagues identified seven monkey teeth encased in 21-million-year-old rocks in the Panama Canal Basin. The teeth, which belong to a previously undiscovered capuchin-like species they have dubbed Panamacebus transitus, represent the oldest evidence of monkeys on the North American continent — and the first evidence of a mammal crossing the ocean that once separated it from South America.

They “never would’ve predicted” it because it sounds too unlikely. Yet “the idea of monkeys rafting around unintentionally on beds of vegetation isn’t as crazy as it sounds.”

No? It’s not allowed to be “crazy” because after all, how did the monkeys get to South America to begin with? Against our will, because it’s against common sense, we’re once again forced to say by rafting:

[M]onkeys had to cross over from Africa. Most scientists believe that happened about 40 million years ago. The Atlantic Ocean would have been a bit narrower than it is now, because of the way the continents have shifted, but it still would have been quite the trip. The monkeys in question were probably carried off to sea on uprooted trees after some kind of storm or other natural disaster.

Ah yes, the theory of animal rafting by uprooted tree and violent storm. The distribution of animals across the globe is often brandished by Darwinists as evidence for common descent. But as Casey Luskin has pointed here, biogeography — the study of that distribution — in fact poses one of the toughest challenges for evolutionary theory. Monkeys are a case in point:

[O]ne of the most severe biogeographical puzzles for Darwinian theory is the origin of South American monkeys, called “platyrrhines.” Based upon molecular and morphological evidence, New World platyrrhine monkeys are thought to be descended from African “Old World” or “catarrhine” monkeys. The fossil record shows that monkeys have lived in South America for about the past 30 million years. But plate tectonic history shows that Africa and South America split off from one another between 100 and 120 million years ago (mya), and that South America was an isolated island continent from about 80 – 3.5 mya. If South American monkeys split off from African monkeys around 30 mya, proponents of neo-Darwinism must somehow account for how they crossed hundreds, if not thousands, of kilometers of open ocean to end up in South America.

This problem for evolutionary biologists has been recognized by numerous experts. A Harper Collins textbook on human evolution states: “The origin of platyrrhine monkeys puzzled paleontologists for decades. … When and how did the monkeys get to South America?” Primatologists John G. Fleagle and Christopher C. Gilbert put it this way in a scientific volume on primate origins:

The most biogeographically challenging aspect of platyrrhine evolution concerns the origin of the entire clade. South America was an island continent throughout most of the Tertiary…and paleontologists have debated for much of this century how and where primates reached South America.

Primate specialist Walter Carl Hartwig is similarly blunt: “The platyrrhine origins issue incorporates several different questions. How did platyrrhines get to South America?” Such basic, vexing questions certainly don’t lend credence to the NCSE’s claims of “consistency between biogeographic and evolutionary patterns.”

For those unfamiliar with the sort of arguments made by neo-Darwinian biogeographers, responses to these puzzles can be almost too incredible to believe. A Harper Collins textbook explains: “The ‘rafting hypothesis’ argues that monkeys evolved from prosimians once and only once in Africa, and … made the water-logged trip to South America.” And of course, there can’t be just one seafaring monkey, or the monkey will soon die leaving no offspring. Thus, at least two monkeys (or perhaps a single pregnant monkey) must have made the rafting voyage.

Fleagle and Gilbert observe that the rafting hypothesis “raises a difficult biogeographical issue” because “South America is separated from Africa by a distance of at least 2600 km, making a phylogenetic and biogeographic link between the primate faunas of the two continents seem very unlikely.” But they are wedded to an evolutionary paradigm, meaning that they are obligated to find such a “link” whether it is likely or not. They argue that in light of “[t]he absence of any anthropoids from North America, combined with the considerable morphological evidence of a South American-African connection with the rodent and primate faunas” that therefore “the rafting hypothesis is the most likely scenario for the biogeographic origin of platyrrines.”

In other words, the “unlikely” rafting hypothesis is made “likely” only because we know common descent must be true.

To borrow a famous image from Sherlock Holmes, the instance with the Channel Island foxes is a case of the dog that didn’t bark in the night. From “The Adventure of the Silver Blaze,” centered on a race horse gone missing:

Gregory (Scotland Yard detective): “Is there any other point to which you would wish to draw my attention?”

Holmes: “To the curious incident of the dog in the night-time.”

Gregory: “The dog did nothing in the night-time.”

Holmes: “That was the curious incident.”

The dog didn’t bark because it knew its owner. The foxes didn’t raft because, under evolutionary theory, they didn’t need to. Monkeys did raft, even across a whole wide ocean, because evolution required it. On other hand, if the theory needed foxes to do so, you can be sure they would obediently hop aboard. It should be the facts that drive startling conclusions, not the theory that’s supposed to explain the facts. But with evolution the roles of fact and theory are often reversed.

Animals do the most striking things, like sailing across oceans on their own, on demand. These are theory-driven “facts,” not a fact-driven theory. The non-rafting foxes are the thing that gives the game away. They are, as Holmes says, the curious incident.

Dogs, by the way, like horses and foxes, are not thought to raft. Not yet!

Photo: Island fox (Urocyon littoralis), by National Park Service, US Department of Interior [Public domain], via Wikimedia Commons.

David Klinghoffer

Senior Fellow and Editor, Evolution News
David Klinghoffer is a Senior Fellow at Discovery Institute and the editor of Evolution News & Science Today, the daily voice of Discovery Institute’s Center for Science & Culture, reporting on intelligent design, evolution, and the intersection of science and culture. Klinghoffer is also the author of six books, a former senior editor and literary editor at National Review magazine, and has written for the Los Angeles Times, New York Times, Wall Street Journal, Washington Post, Seattle Times, Commentary, and other publications. Born in Santa Monica, California, he graduated from Brown University in 1987 with an A.B. magna cum laude in comparative literature and religious studies. David lives near Seattle, Washington, with his wife and children.

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