Evening Republican, Volume 23, Number 132, Rensselaer, Jasper County, 1 June 1920 — Was There Once an Antillean Continent? [ARTICLE+ILLUSTRATION]

Was There Once an Antillean Continent?

IKSjraAPTAIN H. E. ANTHONY, B associate curator of the L y B department of mammals ___H of the American museum of natural history, has J ust returned from a four--15 &£l month's exploration trip I through the West Indies. The museum has been carrying on active work in the West Ind!*** for several years, having been especially energetic since 1916, when the discoveries of fossil mammals of Porto lUco disclosed the possibilities awaiting West Indian research. Naturalists have always been attracted not so much by the intrinsic Interest of the forms of animal life to be found in the Antilles, as by the more absorbing problem: “How did life arrive on the Islands?" It was to seek further light on this question In particular that Captain Anthony was sent to continue the investigations which he had already begun in this region. He retums with a great accumulation of material and data bearing on the problem. Questioned concerning the various theories of the arrival of life on the islands, Captain Anthony said: “It was at first assumed that the islands, lying outside the limits of the continental shelf, .were of oceanic origin and were built up by coral growth or elevated by volcanic or seismic activity. But if this were true, the Islands would be devoid of all forms which might arrive on oceanic 'islands in the natural course of events and those lower forms of life whose disposal is subject to such fortuitous agencies of distribution as hurricanes, water spouts, etc., which transport the eggs from place to place. But the fact is that other forms of life than these are to be found on the Islands. The mammals are the most poorly represented group of the higher animals of the West Indies, yet include varieties which might be expected to encounter great difficulty in crossing the long stretches of sea which it would be necessary for them to traverse before they could establish themselves on the newly-created islands. For this very reason the mammalian fauna of the West Indies in its relation to the continental fauna furnishes one of the best points for an attack on the problem.

“Throughout the thousands of islands in the Antillean group there are only a few mammals, aside from bats, to be encountered. The remarkable poverty of this fauna has been the cause of much comment among nat■ralists. That the condition of the fauna today does not truly represent the mammalian history of the islands lias been suspected for some time, and the efforts of the museum have been especially directed toward ascertaining the complete history of the West Indian mammals from earliest times. Assemblages of fossil mammals have been discovered in Porto Klco and Cuba, indicating the possibHity that at one time the West Indies a much larger mammal inhabitation than today. “These fossils, which are of ancient types and strange ancestry, strongly suggest, if not the existence of some mainland connection far back in the geological age, at least the union at some time of most of the Greater Antilles into a large Antillean continent. This continent, if it existed, must have Uta In the Gulf of Mexico and the Caribbean sea, with the longer axis east and west, and must have been an Important land mass with large livers and mighty mountain ranges

rising, perhaps as high as 20,000 feet or more above sea level. “This theory of the mountains and rivers rests on Spencer’s studies and charts of the ocean floor of the region. Spencer concluded from the conformation of the sea bottom that in tertiary times there must have been ah elevation of this surface of somewhere between 1% and 2% miles. As the ridges of the sea bottom seem to follow out the general direction of the mountain ranges at present existing on the islands, he derived the theory that the under-sea ridges and the island ranges were originally parts of the same system. As the island ranges have an altitude of from 7,000 to 8,006 feet, the mountains of the now disappeared continent would have been something like 20,000 feet high. The channels in the under-sea surface, running at right angles to the ridges seem to have been cut by great rivers flowing down the mountain sides.

“To the eastward this continent took in the recently acquired Danish West Indies, while to the westward its limits must have taken in part of what is now Central America. Because of the strategic position of Jamaica in its relation to the Central American mainland and to such a hypothetical Antillean continent, it was highly important that the fossil fauna of Jamaica be explored.” He was successful in conducting such an exploration, and was able to verify in a most satisfactory manner his belief that the island would be found to have a fossil fauna. He secured several fossil mammals new to science, which, found in Pleistocene formations, must date back approximately 100,000 years. Most of the materials were secured in exploring the limestone caves, and the mammal remains were found cemented in a very hard limestone breccia from which they 'could be extracted only after laborious quarrying. The greater part of the collection was brought back to the museum on large blocks of limestone and much time and work will be necessary before the material can be satisfactorily identified and conclusions drawn. Enough has been exposed, however, to show that Jamaica was formerly the home of one or two gigantic rodents. larger than any living today—animals of a heavy-bodied, slow-mov-ing type, whose closest ancestors lived away back on the Santa Cruz formation of Patagonia. Fossil terrapins,

tortoises and crocodiles were also found. A surprising feature of the exploration conducted* by the expedition was the failure to find any mammals closely related to those found either on Cuba or on Porto Rico. This suggests the possibility that Jamaica may not have formed part of the old Antillean continent, but may have existed as an eastern peninsula jutting out from Honduras. A second theory (but one which has few adherents among recent day zoologists) is that Jamaica was Isolated from all other land and received its mammal denizens as waifs on life rafts, floating masses of vegetation swept down the large continental rivers. ■ In addition to Its success in collecting the fossil fauna, the expedition obtained a large collection of the living animal forms. Only one land mammal is living on Jamaica today—the Indian Coney (Geocapromys brownei) —and even that had been thought practically extinct. For the introduction of the Mongoose on the island, late in the last century. In an attempt to exterminate the rats, has resulted in the extinction of many of the native animals.

Captain Anthony, In describing the method of hunting the Indian Coney; said: “In order to get this animal, which Is" a rat-like creature the size of a cat, the collectors went up Into the high mountains and lived with the natives, hunting'the coney in the primitive fashion with small dogs. The dogs tracked the mammal to its hole in the rocks under some large tree, and there, amidst great excitement, the quarry was dug out. If dhe hole is a fairly large one, the dog can enat once and come to grips with its prey, but more often a man has to pull away rocks and enlarge the hole. The natives get as thoroughly aroused as the dogs, and the scene at the finish is one worthy of larger game. When, the dog finally gets close enough to the coney a fight ensues — for the animal is plucky. When the hunters decide that the dog has secured his grip they draw him out by his tail or a hind leg and take the coney away from.him.” Captain Anthony brought back with him more than seven hundred specimens of bats, as well as collections of reptiles and birds. This material, when properly worked up, will undoubtedly throw much light on West Indian natural history, and the results will help to direct the course of future investigations in that region. As the prophecies concerning Jamaica have borne such gratifying fruit, natural history exploration on the islands will receive a great stimulus. The expedition encountered a very interested co-operation on the part of the people of Jamaica, everywhere meeting with ready assistance and unfailing courtesy. All the important areas of the island were visited with the idea of making the collection as complete as possible. Captain Anthony reported that the tourist travel to Jamaica had been unusually heavy this winter, overtaxing the steamship service and the island’s hotel accommodations. One of the burning topics of the day, there —and by no means a one-sided question —is “How do the Americans regard the possible acquisition of Jamaica by the United States?”