Reprinted from the JAMAICA NATURALIST CITATION: Kelly, Daniel. The Threatened Flowing Plants of Jamaica. Jamaica Naturalist, Vol. 1, 19-26. 1991 Published by the NATURAL HISTORY SOCIETY OF JAMAICA http://naturalhistorysocietyjamaica.org/ NHSJ The Threatened Flowering Jamaica is a small islan d with a rich flora: some 3000 species of flower­ Plants of Jamaica: ing plants (native and naturalized). This richness By DANIEL KELLY A Reappraisal School of Botany reflects its tropical location, Trinity College and its wide range of University of Dublin alt itude - the Blue Moun­ tains, rising to 2256 m, are 1. The Uniqueness of the Jamaican flora very h igh for the size of the island. The mountainous topography results in a emerge in the mid-Miocene period, by driftwood and other debris. diversity of local climates, some 20 million years ago. Since its (Such "rafting" must have been a with wide variations in emergence, the island has apparently major means of arrival for the never had any land connection to the terrestrial faun a). rainfall and temperature. continents or to other islands. With the passage of many Further diversity is added This means that the flora had generations, new traits appear, new by the geological complexity to come in by migration across a mutations, new combinations of of the island, giving marine barrier that was probably genes and may spread through a contrastin g landscapes of never less than 100km wide. The population. Other traits will dimin­ flora will have constituted itself ish and disappear, because they limestones, shales and other gradually, but we have no record of are less well adapted to local rock-typ es. the sequence involved. The first land conditions, or simply through plants to become established were random "genetic dri ft". Gradually, A striking feature of the probably species of lichens, mosses many members of the island flora flora is the large number of species and ferns: small plants that are dis­ became distinct from the continen­ found nowhere else in the world, persed by spores, can eke out a living tal species from which they were i.e. endemic species. Jamaica has on bare rock. These 'pioneers' will derived. In the same way, many about 822 endemic flowering plan t have found an inhospitable land: no forms on this island gradually species - over a quarter of the total soil, no shade. For a prolonged became different from those on the flora. Another substantial element period the flora must have been other islands. A unique biological in the flora consists of species that limited to a few highly tolerant enti ty - an endemic- is formed: a are found only in Jamaica and the species something like the flora of the plant (or animal) found nowhere immediately adjacent islands, i.e. offshore cays today. As vegetation else in the world. are Greater Antillean endemics cover developed, and the rocks This is the general way in (e.g, the Dildo Cactus, Stenocereus weathered to form soil, conditions for which Jamaica's peculiar flora and hystrix>. Of course, Cuba and plant growth will have gradually fauna arose. On the other islands Hispaniola each has a largerflora improved, and the flora will have and on the mainland we find forms than Jamaica, and each has its own become more diverse. Flowering that are more or less similar, and rich endemic flora. plant species can immigrate by a yet distinct. To take a familiar In order to understand the variety of means. Many seed s must example, the palm genus Roystonea: constitution of the Jamaican flora, have arrived carried by birds, either Jamaica has two native species, R. we must note the island's position, adhering to their legs or plumage, or princeps (Swamp Cabbage) and R. at a considerable distance from the carried within their guts (many berry­ altissima (Mountain Cabbage), both mainla nds of Central and South bearing plants have achieved long­ endemic; Cuba has several endemic America. The geological history of distance dispersal by means of their species, includin g R. regia (Royal the island is complex. The land of edible fruits). Many seeds will have Palm); whilst another species, R. Jamaica was entirely submerged been carried by wind: plumed seeds, oleracea (Palmiste) is distributed benea th the sea in late Oligocene or tiny du st-like seeds such as those of over a wide area of northern-South and Eocene times (when the grea t orchids. Yet other plants will have America (extending up as far as thicknesses of White Limestone arrived floating on the sea, either as Barbados). The distinctions in­ were laid down). Land began to re- indivdual seeds or on "rafts" formed volved may be only slight, in'which 19 He's Jamaican Too When we harm our environment, we harm ourselves. Like this Jamaican Owl (Pseudoscops Grammicus or Patoo), every tree, river, fish and bird...every creature of Nature contributes to life on this planet and deserves our respect. In Jamaica we must take care to sustain the quality of our air, sea and land. Shell is helping the cause of environmental conservation in Jamaica. Shell helped found the Jamaica Junior Naturalists which teaches our children to value our country's plant and animal life. Shell uses its calendar.to encourage the protection of endangered marine life. Company representatives have discussed with community organizations the need to balance economic progress with environmental preservation. They also have urged business groups to "bring the environment into the boardroom." Within its own operations, Shell uses many opportunities to show its customers how to use its products safely...and in ways that won't hurt the environment. It was Shell's marketing initiative that brought unleaded gasoline to Jamaica. But Shell knows it still has some way to go in its own operations. The company conducted an exhaustive environmental audit at all its installations, then hired a full time, in-house environmentalist to carry out the improvements. Everyone of us ... children, professionals, the man & woman in the street... must help make sure we have a healthy environment. After all, we're all Jamaicans too! I!JJJ\. The Shell Companies in Jamaica ~ Rockfort, Kingston 2. Tel: 928-7301-9/928-7231-9 Table 1: I - The flowering plant flora of the Greater Antilles: endemism and evaluation of threat. All figuresrepresent current estimates. Data for other islands extracted from Davis et at. (1986),Zanoni (1989) Jamaica Cuba Hispaniola (Dominican Republic + Haiti) Area (km2) 11,425 114,524 76,191 Human population 2,290,000 9,966,000 12,520,000 Mean population 200 87 164 density (people per km2) Total numberof species 3000 6140 5000 Number of endemic species 822 3150 1500-1650 Proportion of endemics 27% 51% 30-33% in total flora Number ofthreatened 256 322 >273 species (Vulnerable, (tiqures for D.R. only) Endangered or apparentlyextinct) Proportion ofthreatened 31% 10% >16% species in total endemicIlora. case we treat each entity as a .Jamaican Hutia or Coney, G. broumii), species of flowering plants. variety or a subspecies; or the The evolution of the mammalian As we noted, the geology distinction may be sufficiently fauna of the West Indies has been and terrain of Jamaica is highly marked to warrant treating each as ascribed to "rare immigration events diverse. There are significant · a different species. (The "rank" followed by extensive adaptive barriers to the migration of plants accorded by taxonomists - var iety, radiations" (Morgan & Woods 1986). from one part of the island to subspecies or species - is often a Some plant families have another. For example, the lime­ matter of debate). shown a greater tend ency to evolve stone block of the John Crow The evolution of distinct endemics than others. Among the Mountains at the east end of the species on different islands of the palms (Palmae), 9 out of 10 species island is now cut off from the lime­ West Indies, through prolonged native to Jamaica are endemic. Of the stones of the middle and west of isolation, has also occured in the 15 native species of cacti (Cactaceae). the island by the siliceous mass of fauna. Take some of the small 6 are endemic to Jamaica, 4 extend the Blue Mountains. The complex non-migratory birds: among the also to the Cayman Islands, and 2 rainfall pattern is a further limita­ Todies (Todus spp.), Jamaica, Cuba extend to others of the Greater An­ tion to plant distribution within and Puerto Rico has each a single tilles. Endemism is relatively low in the island. So we find the further endemic species, and Hispaniola the lower plants. For instance, there feature of localized end emism has two endemic species; among are only 67 endemic species out of the within the island flora . In many of the Hummingbirds (Trochilidae), 579 species of pteridophytes (ferns the larger genera, distinct species or most species are confined to a and fern allies) in the Jamaican flora subspecies have evolved in differ­ single island or a small group of (Proctor 1985). In lower plants disper­ ent parts of the island. This "evolu­ islands (Bond, 1974). Island sal is by spores instead of seeds; the tionary radiation" is very striking endemism was also well-developed sea represents less of a barrier to in a number of groups (Table 2). among rodents, e.g. the genus migration, and species tend to have The figures given must not be Geocapromys (which includes the wider geographical ranges than do taken as definitive: further study 21 Table 2: I Genera of flowering plants showing remarkable evolutionary radiation within the island of Iamaica The family to which the genus belongs is given in brackets.