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Aquariums 1. Introduction
& Reptiles Cichlid fishes, along with Darwin’s finch-

AT CR ANBOURNE es and Caribbean Anolis lizards, repre-
sent a key vertebrate model system for
For the right advice and all your understanding the evolutionary assembly
aquarium needs of biodiversity [1,2]. Despite the group’s
prominence in biological research, a con-
OPEN 365 DAYS sistent macroevolutionary time scale and
8 am-6 pm biogeographic history for cichlids has
remained elusive [3-6]. For nearly four
Full range of aquarium, tropical and coldwater fish; decades, the study of deep cichlid evo-
Large range of reptiles and accessories; lutionary history has been dominated by
vicariance models of biogeography that
Tanks and cabinets; Full set-ups from 2ft to 8ft; link the present-day distribution of the
Wide range of live and frozen foods; Plants; group to the tectonic fragmentation of
Full range of conditioners; Free water testing. the supercontinent of Gondwana during
the mid to late Mesozoic (ca 135-90 Ma;
14 Cooper Court, Cranbourne, VIC figure 1) [8,9]. Continued investigation of
cichlid intrarelationships, including phy-
03 5995 5066 logenetic analysis of molecular sequence
data, has shown congruence between the
aquariumsatcranbourne.com.au order of divergences among geographi-
cally restricted cichlid clades and proposed
6 sequences of continental break-up [10].
The vicariance hypothesis of cich-
lid historical biogeography has become
so entrenched that the rifting history
of Gondwana is routinely used to cali-
brate teleost molecular clocks [3,6], with
the consequence that this hypothetical
scenario now directly influences estimates
of the evolutionary time scale for more
than half of all modern vertebrate diversity.
If the distribution of modern cichlids
is attributable purely to Gondwanan break-
up, then it necessarily follows that the com-
mon ancestor of all living cichlids originated
no later than the final separation between
Madagascar-India and South America-
Africa-Arabia. Current geological evidence

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