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above sea level some 20 Ma (Fig. 2.9a), although
their construction process began almost 70–80 Ma
in the Late Cretaceous Era (Anguita et al. 2002).
This first island was likely colonized and populated
predominantly from the nearby African mainland,
some 100 km away. Some 4 million years later
(c.16 Ma), the basaltic massives of Femés (Los
Ajaches) emerged, forming the first shield of what
became the island of Lanzarote, which was thus
available for colonization simultaneously from the
mainland and the older island.
The expansion of the archipelago towards the
Atlantic Ocean began 2 million years later, with the
emergence of Gran Canaria (Fig. 2.9b), and was con-
solidated with the appearance of La Gomera c.12 Ma
and Famara c. 10 Ma (Fig. 2.9c). These islands, much
larger and higher than today, have suffered many
catastrophic landslides during their geological
history (below). The next major additions to the
archipelago were the basaltic massifs of Teno,

Adeje, and Anaga, which emerged about 8 Ma

between La Gomera and Gran Canaria, forming the

corners of what was to become the island of Tenerife

(Fig. 2.9d). It appears likely that Teno and Adeje were

mainly populated from La Gomera, whereas Anaga

was mainly colonized from Gran Canaria.

Interestingly, some 10% of the endemic plants of the

Canaries are restricted to one or more of the palaeois-

lands of Tenerife, likely including a mix of early

diverging and recently diverging lineages (Trusty

et al. 2005).

Some 3.5 Ma, the catastrophic Roque Nublo ash

flow is thought to have almost completely sterilized

Gran Canaria, perhaps with the exception of two

localized refugia (Marrero and Francisco-Ortega,

2001 a, b). If so, the recolonization process will have

started both from those refugia, and, especially for

the mountain and summit ecosystems, from the

nearby island massifs of Anaga and Jandía, respec-

tively 60 and 90 km away.

28 ISLAND ENVIRONMENTS

AFRICA

F

20 Ma

(a)

AFRICA

F

C

L

AFRICA

G C

F

L Famara

Femés

AFRICA

G

T

C

F

L Famara

Anaga Femés

Adeje

Teno

AFRICA

P

G

T

C

F

L

AFRICA

Canary Islands

P

H

G

T

C

F

L

Present

15 Ma 1 Ma

5 Ma

10 Ma

(b)

(c)

(d)

(e)

(f)

Figure 2.9Sequence of emergence of the islands of the Canarian archipelago (Modified from Marrero and Francisco-Ortega 2001, Fig. 14.1).
LLanzarote, FFuerteventura, CGran Canaria, TTenerife, PLa Palma, GLa Gomera, HEl Hierro.