64 THE BIOGEOGRAPHY OF ISLAND LIFE
Selected Central and South Europe fossil taxa and corresponding palaeoendemic Macaronesian laurel forest taxa (source: Sunding 1979,
slightly modified). Sunding’s interpretation of the Canary Islands biogeography is now regarded as flawed in a number of respects: e.g. the
supposition of past land connections between the eastern islands and the mainland, and the notion of woodiness in normally herbaceous
genera as a relictual trait (Carlquist 1995)Central–South European fossil taxon Corresponding Macaronesian taxon
(if different from the fossil)Adiantum reniforme
Apollonias aquensis Apollonias barbujana, A. ceballosi
Asplenium hemionitis
Clethra berendtii Clethra arborea
Ilex canariensis
Laurus azorica Laurus azorica, L. novocanariensis
Maytenus canariensis
Myrsinespp. Myrsine canariensis
Ocotea heerii Ocotea foetens
Persea indica
Picconia excelsa
Smilax targionii Smilax canariensis
Viburnum pseudotinus Vinurnum tinusssp.rigidum
Woodwardia radicans
Other laurel forest species still extant in Iberia and present in Macaronesia:
Culcita macrocarpa,Davallia canariensis,Erica arborea,Myrica faya,Prunus lusitanica,Trichomanes speciosum,Umbilicus heylandianuscautions, some authors have attributed relictualism
to features (e.g. woodiness in herbaceous taxa)
and lineages that are actually recent products of in
situevolutionary change on islands. Indeed, the
Canaries in particular are characterized by plenty
of examples of neoendemic speciation and
radiation (Santos-Guerra 1999).In the last few hundred years, human
settlement and deforestation within
Macaronesia has led to the loss of most of
the laurel forest, especially in the Azores, and
today large remnants are only to be found in
Madeira and the western Canaries, particularly
on La Gomera.species now endemic to an island or island group
have actually evolved in situ. Cronk (1992) refers to
such relict or stranded forms as palaeoendemics,
whereas species that have evolved in situare
neoendemics. As with all such distinctions, this is
an oversimplification, as it implies a lack of change
in either island or mainland forms, respectively,
which may not strictly be the case.
It should be noted that the significance of relict
forms or relictual ground plans as against in situ
evolution is a topic that generates considerable
heat, and indeed some of the more keenly contested
issues in biogeography (cf. Heads 1990; Pole 1994;
Carlquist 1995; Winkworth et al. 2002). Cronk (1992)
argues that ancient, taxonomically isolated, relict
species should hold a special importance in conser-
vation terms, in that their extinction would cause a
greater loss of unique gene sequences and morpho-
logical diversity than the extinction of a species
with close relations.
There is no doubt as to the importance of
endemic forms on particular islands, although as
taxonomic work continues, estimates of the degree
of endemism for an island group vary. Figure 3.10
demonstrates this for the flora of the Galápagos.
Since fairly complete inventories became avail-
able, the number of known endemics has changed
relatively little: the refinements come from