Nirav Patel
1/25/11
Biogeography Week 1
1)Xu, L., Han B., Damme K.V., Vierstraete, A., Vanfleteren, J., Dumont, H. 2011. Biogeography
and evolution of the Holarctic zooplankton genus Leptodora (Crustacea: Branchiopoda:
Haplopoda). Journal of Biogeography (J.Biogeogr.) (2011) 38, 359-370. {don’t forget to italicize
genus and species names.}
Bo-Ping Han is with the Institute of Hydrobiology at Jinan University, Guangzhou, China and
Henri J. Dumont is with the Department of Biology at Ghent University in Ghent, Belgium.
2) What is the phylogeographic history of the Holarctic carnivorous genus Leptodora? {Good
job here} Is the species genetically homogenous across its geographic range rich in topographic
and climactic barriers, if not, what geological and palaeoclimatic events shaped its phylogeny?
3) The Holarctic genus Leptodora is unique because it is the sole extant of representative of the
order Haplopoda. Leptodora richardi is widespread over regions in Japan, Korea and China.
Numerous mountain chains, hydrogeographic discrepancies, saline/marine environments are
barriers for Leptodora. The river plankton colonize the newly created water bodies and its resting
stages find itself drifting themselves along major rivers, with downstream migration through
gravity, upstream through phoretic means and inside vertebrates. The preferred habitat for these
adults within this zooplanktivorous animal is stagnant water, from medium sized water to big
lakes, as studying eutrophic and oligotrophic lakes in Germany. The distribution of Leptodora
has not been viewed in the lens of using the information from the genome. L. kindtii is spread
over parts of Europe, and in populations in Europe and Asia Minor. Leptodora is absent from
Iran, but its present in the north. The isles the groups is present, in China L. richardi occurs
naturally. Leptodora also penetrates the Arctic zone, and is widespread in the United States and
Canada.
4) They sequenced a mitochondrial (cytochrome c oxidase subunit 1) and a nuclear (elongation
factor-1a) gene, and meshed this data with the molecular information and geological and
paleoclimatological data, given the different areas in the world where they isolated the species of
Leptodora. Haplotype networks and phylogenetic trees were constructed using a Bayesian and a
likelihood approach, with a molecular clock being applied.
5) Leptodora has three clades. Leptodora richardi is the most thermophilic of the three,
extending from the Tropic of Cancer in the south to the Heilong Basin in the north. L. kindtii is
more cold-water adapted than its eastern Mediterranean subclade. “West European” and
‘Chinese’ clades are separated by a hybrid zone in Siberia and European Russia. These hybrids
have the DNA from these two species as can exist in low temperatures and they may have
formed as recently as the Holocene hypsithermal. The figure that I would have added is:
Nirav Patel
1/25/11
Biogeography Week 1
6) There were some conclusions made about the North America taxon, like the conclusion that
the taxon was still living in isolation, but it is clearly stated within the study that North America
wasn’t studied. {Rats! That’s where I’ve seen them.}
7) The observations made with the molecular clock including the other data in the East Asian and
European populations holds fairly true, as now we know that during the Alpine folding in the
Pleistocene, the L. kindtii moved eastwards across Siberia and back, the population in Xinjiang is
a remnant of an early wave coming from western Europe, crossed the Dzungarian Gates during a
humid mid-Pleistocene event, and later aridity isolated the population there. The Euro-Siberian
hybrid that originated during the hybrid zone may engulf all populations.
Ever see a Leptodora?They can be up to 21 mm long:
Nirav Patel
1/25/11
Biogeography Week 1
and here is a more typical Cladocera, Daphnia. It is about 1.5 mm long.
Nice summary – especially once you add the map.