11th ICRS Abstract book - Nova Southeastern University

Oral Mini-Symposium 26: Biodiversity and Diversification of Reef Organisms
26-13
Age And Origin Of Hawaiian Endemic Fishes in The Papahânaumokuâkea Marine
National Monument
Zoltan SZABO 1 , John RANDALL 1 , Randall KOSAKI 2 , Brian BOWEN* 3
1 Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe, HI,
2 Papahânaumokuâkea Marine National Monument, Honolulu, HI, 3 University of Hawaii,
Hawaii Institute of Marine Biology, Kaneohe, HI
The Hawaiian Archipelago has one of the highest levels of marine endemism (25% for
fishes) and is among the most isolated reef habitats in the world. In this research
program, we are examining the age and source of colonization events that enhance
Hawaiian biodiversity, especially in the new Papahânaumokuâkea Marine National
Monument. Three of these Hawaiian endemics (HE) are blennies with an unambiguous
sister species in the Indo-West Pacific (IWP) which allowed us to resolve the age of
colonization events. Based on a 659 bp fragment of mitochondrial cytochrome b, we
observed approximately d = 7% sequence divergence between Cirripectes vanderbilti
(HE) and C. variolosus (IWP) and about the same level of divergence between
Plagiotremus ewaensis (HE) and P. rhinorhynchos (IWP). Between Plagiotremus goslinei
(HE) and P. tapeinosoma (IWP) we observed d = 0.3% (2 bp differences) indicating a
very recent arrival. A conventional molecular clock for fishes places the first two
colonization events at approximately 3.5 million years ago, and the third event at
approximately 150,000 years ago. Ongoing research will indicate whether Johnston Atoll,
800 km south of Hawaii, is the essential gateway into the archipelago, and whether a
pulse of colonization occurred at 3.5 million years before present. Our finding for P.
goslinei may prompt a re-examination of taxonomic status.
26-14
How Useful Is Panbiogeography in Deconstructing Philippine Coral Reef
Biogeography?
Benjamin VALLEJO JR* 1
1 Institute of Environmental Science and Meteorology, University of the Philippines,
Quezon City, Philippines
The Philippines is considered at the center of global coral reef biodiversity. Recent
studies indicate that the Verde Island Passage in Southwestern Luzon has extremely high
taxonmic diversity per unit area. More recent research indicate that several areas in the
central Philippines have similar levels of taxonomic richness most notably in molluscs.
The existence of several diversity massings within archipelagic seas or basins in the
Philippines is a major biogeographic pattern that strenthens the theory that these seas are
important biogeographic regions. These patterns are coincident with major tectonic
features. As island integration seems to be the most parsimonious theory to explain
Philippine biogeography, this necessitates a more integrative theory to explain these
spatial patterns of marine biodiversity. A panbiogeographic hypothesis is thus presented.
26-15
Atlantic Reef Fish Biogeography And Evolution
Sergio FLOETER* 1 , Luiz ROCHA 2 , Ross ROBERTSON 3
1 Ecologia e Zoologia, UFSC, Florianopolis, Brazil, 2 HIMB, University of Hawaii, Kaneohe, HI,
3 Smithsonian Tropical Research Institute, Panama, Panama
How and when areas of endemism of the tropical Atlantic Ocean were formed? How do they
relate to each other? What are the spatio-temporal components of diversification? We tried to
shed light into these questions by analyzing the distributions of 2605 reef fishes in 25 areas of
the Atlantic and southern Africa and a collection of 27 recently published phylogenies of
various Atlantic reef fish taxa. Phylogenetic (proportion of sister species) and distributional
patterns (number of shared species) are generally concordant with recognized biogeographic
provinces. The highly uneven distribution of species in certain genera appears to be related to
their origin, with highest species richness in areas with the greatest phylogenetic depth.
Diversity buildup in the Atlantic involved (1) diversification within each province, (2) isolation
as a result of biogeographic barriers, and (3) stochastic accretion via dispersal between
provinces. The timing of cladogenesis is not concordant among taxonomic groups, indicating
that no single vicariant event explains the observed divergences. The three soft (non-terrestrial)
inter-regional barriers (mid-Atlantic, Amazon, and Benguela) clearly act as “filters” by
restricting dispersal but at the same time allowing occasional crossings that eventually become
new species. Fluctuations in the effectiveness of these filters, combined with ecological
differences among provinces, apparently provide a mechanism for much of the recent
diversification of reef fishes in the Atlantic. Fish life history attributes like spawning mode,
body size and depth range are differentially affected by the soft barriers as revealed by the
analyses of trans-barrier species. Our dataset indicates that both historical events (e.g. Tethys
closure) as well as relatively recent dispersal (with or without further speciation) have had a
strong influence on Atlantic tropical marine biodiversity and have contributed to the
biogeographic patterns we observe today, however, examples of the latter process outnumber
the former.
26-16
A Regional Scale Diversity-Environment Relationship For Pacific Coral Reef Fish
Communities
Laurent VIGLIOLA* 1,2 , Serge ANDREFOUET 3,4 , Michel KULBICKI 5 , Christine
KRANENBOURG 6 , Pierre LEGENDRE 7 , Pierre LABROSSE 2,8 , Samasoni SAUNI 2,9 , Pierre
BOBLIN 2
1 Institut de Recherche pour le Développement (IRD), Plouzane, France, 2 Secretariat of the
Pacific Community (SPC), Noumea, New Caledonia, 3 Institut de Recherche pour le
Développement (IRD), Noumea, New Caledonia, 4 Institute for Marine Remote Sensing
(IMaRS), St. Petersburg, 5 Institut de Recherche pour le Développement (IRD), Perpignan,
France, 6 Institute for Marine Remote Sensing (IMaRS), St. Petersburg, FL, 7 Université de
Montréal, Montreal, QC, Canada, 8 Institut Mauritanien de Recherches Océanographiques et des
Pêches (IMROP), Nouadhibou, Mauritania, 9 Pacific Islands Forum Fisheries Agency (FFA),
Honiara, Solomon Islands
Predicting the response of biodiversity to ongoing global and local changes in the environment
is a challenging, yet necessary step to identify the most effective schemes for conservation and
sustainable use. The present study combines in situ and remotely sensed data across 10 Pacific
Island Countries and estimates a diversity-environment relationship for coral reef fish
communities across this 5500 km longitude by 2500 km latitude region. Reef fish diversity and
32 associated environmental variables were recorded by underwater visual censuses following a
stratified sampling design. The environmental matrix was augmented with an additional 40
variables derived from remotely sensed geomorphologic maps. Measurements were made
within a moving window, effectively collecting information at multiple spatial scales. A general
linear model revealed that the combination of nine environmental variables accounted for 69%
of species richness variability. Fish diversity increased with depth, habitat complexity, reef
diversity at 200-m scale, and variation in reef composition at 20-km scale. Diversity was greater
on reef slopes than on flats and decreased with the amount of land within a 2 km 2 area, reef
connectivity at 2-km scale, variation in reef composition within a 200 km 2 area, and the distance
to the Indo-Australian centre of biodiversity. Contemporary distribution patterns of biodiversity
are a function of species origin, dispersal, and survival. By combining proxies of these factors at
multiple spatial scales, this study indicates that good predictions of biodiversity can be made for
coral reef fishes of the Pacific region.
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