0198566123.pdf

species numbers may change in fragments follow- ing isolation, we still have a poor grasp of the over- all implications for dive ...

nature of the final demise of the endemic may be unrelated to the driver(s) of the initial range col- lapse. Typically, there ha ...

...from cowpats to South America, it is difficult to see what is not or at some time has not been an island. (Mabberley 1979, p. ...

of continental rock stranded out in the oceans by plate tectonic processes. ●Continental shelf islands are those islands located ...

the lifespan of an island (Stuessy et al. 1998). In con- trast, habitat islands exist typically within complex landscape matrice ...

other, or moving past each other laterally. Relatively few islands are ancient biogeographically; some have experienced a comple ...

14 ISLAND ENVIRONMENTS 12 ° 10 ° 8 ° 6 ° 4 ° 2 ° Longitude West 0 ° Atlantic Irish shelf Ireland Britain North Sea Metres 1000 1 ...

MODES OF ORIGIN 15 Examples of islands corresponding to the three types identified by Wallace, from different oceans of the worl ...

16 ISLAND ENVIRONMENTS thought to have been formed by both mid-ocean ridge and hotspot activity. Setting aside islands of contin ...

MODES OF ORIGIN 17 Box 2.2 The splitting of Gondwanaland and the debate between vicariant and dispersalist explanations in islan ...

18 ISLAND ENVIRONMENTS continental fragment islands like Madagascar, New Zealand, and New Caledonia, are characterized by high e ...

MODES OF ORIGIN 19 long after this continental fragment began its ocean voyaging. Similarly, changing sea level, especially the ...

paucity of sedimentary load in the subducted crust. The Sandwich arc in the south Atlantic involves both basaltic and andesitic ...

atolls, or guyots. The chain extends from the Loihi Seamount, which is believed to be closest to the hotspot centre, through the ...

El Hierro) (Carracedo et al. 1998). It seems that neither idea on its own can explain the origins of this particular archipelago ...

and the final stage is the formation of an atoll, where the original island has disappeared, leaving only the coral ring surroun ...

elevated. Christmas Island in the Indian Ocean exemplifies this. It has been elevated to form a plateau of 150–250 m above sea l ...

archipelago is primarily a result of isostatic or of eustatic changes. However, it is important to recog- nize these complexitie ...

26 ISLAND ENVIRONMENTS 0 5 10 15 20 25 30 Bristol Channel English Channel Cardigan Bay Somerset Levels North Wales 35 10 Depth b ...

amplitude than long-term variation, i.e. the variance within decades is less than the variance within cen- turies, which is agai ...