Pollen movement across central Singapore appears to be maintained, despite forest degradation, fragmentation and urbanisation

Noreen, A. M. E., Niissalo, M. A., Lum, S. K. Y., & Webb, E. L. (2016). Persistence of long-distance, insect-mediated pollen movement for a tropical canopy tree species in remnant forest patches in an urban landscape. Heredity, 5 October 2016 | doi:10.1038/hdy.2016.64

“Given the robust pollinators of Koompassia (e.g. Apis dorsata), pollen movement across central Singapore appears to be maintained even after forest degradation, fragmentation and urbanization.”

Abstract – As deforestation and urbanization continue at rapid rates in tropical regions, urban forest patches are essential repositories of biodiversity. However, almost nothing is known about gene flow of forest-dependent tree species in urban landscapes. In this study, we investigated gene flow in the insect-pollinated, wind-dispersed tropical tree Koompassia malaccensis in and among three remnant forest patches in the urbanized landscape of Singapore.

We genotyped the vast majority of adults (N = 179) and a large number of recruits (N = 2103) with 8 highly polymorphic microsatellite markers. Spatial genetic structure of the recruit and adult cohorts was significant, showing routine gene dispersal distances of ~ 100–400 m. Parentage analysis showed that 97% of recruits were within 100 m of their mother tree, and a high frequency of relatively short-distance pollen dispersal (median~ 143–187 m).

Despite routine seed and pollen dispersal distances of within a few hundred meters, interpatch gene flow occurred between all patches and was dominated by pollen movement: parentage analysis showed 76 pollen versus two seed interpatch dispersal events, and the seedling neighborhood model estimated ~ 1–6% seed immigration and ~ 21–46% pollen immigration rates, depending on patch. In addition, the smallest patch (containing five adult K. malaccensis trees) was entirely surrounded by 42.5 km of ‘impervious’ substrate, yet had the highest proportional pollen and seed immigration estimates of any patch.

Hence, contrary to our hypothesis, insect-mediated gene flow persisted across an urban landscape, and several of our results also parallel key findings from insect-pollinated canopy trees sampled in mixed agricultural–forest landscapes.

Advertisements

Right under our noses! Microhyla laterite, a new and endangered species of frog discovered through an integrative taxonomic approach

Grad student Seshadri reports with jubilation:

Dear Colleagues,

Greetings!

It gives me great pleasure to share this recent publication reporting the discovery of a new species of frog from the Coastal plains along the Southwest part of India.

One would agree that amphibians are among the most fascinating creatures owing to the sheer magnitude of diversity, the enormous range of behaviour and an ecology that we are finding intriguingly intricate. Further, taxonomy and systematics are a fundamental key to documenting biodiversity and in recent years, amphibian species richness in India has grown in leaps and bounds – just a couple months ago, there were reports of new species being discovered from India.

In our rather unique study, we report the discovery of Microhyla laterite, not from the super species rich Western Ghats but from laterite rock dominated areas a sleepy little town of Manipal, Udupi District in Southwest India. This discovery is a case of a new species hidden in plain sight for decades, and all this while, thought to be a variant of the common Microhyla ornata. Using an integrative taxonomic approach spanning genetics, morphology and bio-acoustic comparisons, it was actually easy to tell them apart!

Map showing type locality of M. laterite sp. nov. (Seshadri et al., 2016)
Screenshot 05

The new species has a distribution range that is less than 150 sq. km and as we propose the new species, we suggest assigning it as Endangered (EN) under B1ab(iii),(iv) of the IUCN Red List. This discovery is significant to us because we now have a mascot to champion the cause of conserving laterite habitats which, even on official government records, are listed as “Wastelands”!

The study is perhaps the first in India where species discovery and subsequent description has been undertaken with a citizen engagement program. Mr. Ramit, my co-author is an engineer by training and was conducting outreach activities as part of his novel initiative, “My Laterite, My Habitat”. He noticed these frogs and investigated further with fellow nature enthusiasts Mr. Saurab and Pratik. The three of them are not part of an academic set up but are passionate about nature and its conservation. This led to a collaborative effort with my long term mentor and colleague Dr. Gururaja and his team and we certainly think it is the right step forward in future.

The paper has been published in PLOS One earlier this morning and is hot off the press: Seshadri KS, Ramit S, Priti H, Ravikanth G, Vidisha MK, Saurabh S, Pratik M and Gururaja KV. Microhyla laterite sp. nov., A New Species of Microhyla Tschudi, 1838 (Amphibia: Anura: Microhylidae) from a Laterite Rock Formation in South West India. PLOS One. 9th March 2016.

I hope you will find the paper interesting and as always, I look forward to your criticisms, comments and perspectives on this work.

Have a good day!

Thanking you,

Sincerely
Seshadri

With warm regards
Seshadri K S

PhD candidate
Evolutionary Ecology and Conservation Lab
Department of Biological Sciences
National University of Singapore
14 Science Drive 4
Singapore 117543

Some recent papers by the Biodiversity Crew

Some of the recent publications by the Biodiversity Crew:

  • Chisholm, R. A., Giam, X., Sadanandan, K. R., Fung, T., & Rheindt, F. E. (2016). A robust nonparametric method for quantifying undetected extinctions. Conservation Biology. – A Singapore study.
  • Tang, G. S., Sadanandan, K. R., & Rheindt, F. E. (2016). Population genetics of the olive‐winged bulbul (Pycnonotus plumosus) in a tropical urban‐fragmented landscape. Ecology and Evolution, 6(1), 78-90 – A Singapore study.
  • Chua, M. A., Sivasothi, N., & Meier, R. (2016). Population density, spatiotemporal use and diet of the leopard cat (Prionailurus bengalensis) in a human-modified succession forest landscape of Singapore. Mammal Research, 1-10. – A Singapore study.
  • Huang, D., Hoeksema, B. W., Affendi, Y. A., Ang, P. O., Chen, C. A., Huang, H., … & Yeemin, T. (2016). Conservation of reef corals in the South China Sea based on species and evolutionary diversity. Biodiversity and Conservation, 25(2), 331-344.
  • Symes, W. S., Rao, M., Mascia, M. B., & Carrasco, L. R. (2015). Why do we lose protected areas? Factors influencing protected area downgrading, downsizing and degazettement in the tropics and subtropics. Global Change Biology.
  • Painting, C. J., Rajamohan, G., Chen, Z., Zeng, H., & Li, D. (2016). It takes two peaks to tango: the importance of UVB and UVA in sexual signalling in jumping spiders. Animal Behaviour, 113, 137-146.
  • Xu, X., Liu, F., Chen, J., Ono, H., Agnarsson, I., Li, D., & Kuntner, M. (2016). Pre‐Pleistocene geological events shaping diversification and distribution of primitively segmented spiders on East Asian margins. Journal of Biogeography.
  • Su, S., Lim, M., & Kunte, K. (2015). Prey from the eyes of predators: Color discriminability of aposematic and mimetic butterflies from an avian visual perspective. Evolution, 69(11), 2985-2994.
  • Ho, S., Schachat, S. R., Piel, W. H., & Monteiro, A. (2016). Attack risk for butterflies changes with eyespot number and size. Royal Society Open Science, 3(1), 150614.
  • Webb, E. L., Wijedasa, L. S., Theilade, I., Merklinger, F., Bult, M., Steinmetz, R., & Brockelman, W. Y. (2016). James F. Maxwell: Classic Field Botanist, Inimitable Character. Biotropica, 48(1), 132-133.

    “Max lived in Singapore, studied at NUS and worked at the Singapore Botanic Gardens. He has a lot of ‘fans’ here in Singapore and in SE Asia at large who were saddened by his passing.

    Max was a spectacularly irreverent character but recognized as one of the top botanists in SE Asia; a contrast of a cheerfully abrasive personality but with a deep and genuine concern for plants, conservation and collections-based science. His collection effort over his career included tens of thousands of herbarium specimens.

    His passing has been widely felt.”

    – Edward Webb

“Creating complex habitats for restoration and reconciliation” – Lynette Loke, Peter Todd et al

A new paper out of Peter Todd’s lab: Loke, L. H., Ladle, R. J., Bouma, T. J., & Todd, P. A. (2015). Creating complex habitats for restoration and reconciliation. Ecological Engineering, 77, 307-313.

Simplification of natural habitats has become a major conservation challenge and there is a growing consensus that incorporating and enhancing habitat complexity is likely to be critical for future restoration efforts. Habitat complexity is often ascribed an important role in controlling species diversity, however, despite numerous empirical studies the exact mechanism(s) driving this association remains unclear. The lack of progress in untangling the relationship between complexity and diversity is partly attributable to the considerable ambiguity in the use of the term ‘complexity’. Here, we offer a new framework for conceptualizing ecological complexity, an essential prerequisite for the development of analytical methods for creating and comparing habitat complexity.

Our framework distinguishes between two fundamental forms of complexity: information-based complexity and systems-based complexity. Most complexity–diversity studies are concerned with informational complexity which can be measured in the field through a variety of metrics (e.g. fractal dimensions, rugosity, etc.), but these metrics cannot be used to re-construct three-dimensional complex habitats.

Drawing on our operational definition of informational complexity, it is possible to design habitats with different degrees of physical complexity. We argue that the ability to determine or modify the variables of complexity precisely has the potential to open up new lines of research in diversity theory and contribute to restoration and reconciliation by enabling environmental managers to rebuild complexity in anthropogenically- simplified habitats.

The future of evolutionary diversity in reef corals – Huang & Roy 2015

Ted Webb alerted us this morning with this message, “Danwei has published an important paper in Phil. Trans. R. Soc. B, that looks at threats and future losses of evolutionary diversity across the world’s coral reefs. (PS great use of skull and crossbones on Fig 1!).”

Huang Danwei and Kaustuv Roy have published “The future of evolutionary diversity in reef corals” in the Philosophical Transactions of the Royal Society B, http://dx.doi.org/10.1098/rstb.2014.0010

“One-third of the world’s reef-building corals are facing heightened extinction risk from climate change and other anthropogenic impacts. Previous studies have shown that such threats are not distributed randomly across the coral tree of life, and future extinctions have the potential to disproportionately reduce the phylogenetic diversity of this group on a global scale. However, the impact of such losses on a regional scale remains poorly known.

In this study, we use phylogenetic metrics in conjunction with geographical distributions of living reef coral species to model how extinctions are likely to affect evolutionary diversity across different ecoregions. Based on two measures—phylogenetic diversity and phylogenetic species variability—we highlight regions with the largest losses of evolutionary diversity and hence of potential conservation interest.

Notably, the projected loss of evolutionary diversity is relatively low in the most species-rich areas such as the Coral Triangle, while many regions with fewer species stand to lose much larger shares of their diversity. We also suggest that for complex ecosystems like coral reefs it is important to consider changes in phylogenetic species variability; areas with disproportionate declines in this measure should be of concern even if phylogenetic diversity is not as impacted.

These findings underscore the importance of integrating evolutionary history into conservation planning for safeguarding the future diversity of coral reefs.

Danwei and Roy 2015 Future of evol diversity in coral reefs pdf  page 2 of 11

Danwei and Roy 2015 Future of evol diversity in coral reefs pdf  page 5 of 11

“The behaviour of giant clams” – Pamela Soo & Peter Todd, 2014

20141120 Pamela Soo

Pamela who has not strayed far from marine life, says, “yay, clams! five years later, and most of the searching and editing on his part, my prof [Peter Todd] has finally found a home for my chunky, lengthy stackofa thesis! all the final year moments of madness distilled into nineteen pages of a scientific journal.”

If you’re keen to peek into the madness, see the paper at Springer.com” (full download).

Congratulations and thanks Pam and Pete! I’ll be using it in the LSM1103 Biodiversity mollusca lecture myself!

Pamela Soo

Photo by Creative Kids.

Butterfly ‘eyespot’ research by Antónia featured on ScienceDaily

Congratulations to Associate Professor Antónia Monteiro and colleagues on the publication of their latest paper, “Nymphalid eyespot serial homologues originate as a few individualized modules” in the Proceedings of The Royal Society B.

Butterfly spots

Diversity of butterfly eyespot numbers and location in the Family Nymphalidae (Oliver et al., 2014)

The paper was highlighted on ScienceDaily in “Butterfly ‘eyespots’ add detail to story of evolution“. The first author, Jeffrey Oliver, a postdoctoral scholar in the Department of Integrative Biology of the Oregon State University College of Science stated that the study indicated how continued mutations allowed eyeposts to move to different positions on the wings to perform a different function from its original placement. With the help of butterfly eyespots, we are inching closer to understand the existence of serial homologues and even the fundamentals of evolution.

For full citation: J. C. Oliver, J. M. Beaulieu, L. F. Gall, W. H. Piel, A. Monteiro. Nymphalid eyespot serial homologues originate as a few individualized modules. Proceedings of the Royal Society B: Biological Sciences, 2014; 281 (1787): 20133262 DOI: 10.1098/rspb.2013.3262