How well do we know our biodiversity? A case study of wild mammals from Colombia
Species checklists provide basic information for taxonomic and geographic studies, and usually, are the first tool for those involved in wildlife management and conservation. Precise species records and taxonomic identifications are important to improve the accuracy of species distribution models, identify priority habitats, establish bases to monitor ecosystems, and mitigate human impacts. However, the use of species checklists is constrained by the completeness and accuracy of updated information.
Last year, I worked with Hector Ramirez-Chaves (PhD student at UQ) and other colleagues analysing distributional records of some mammal species from Colombia. In a recent paper, we clarified some issues concerning the distribution and the taxonomic identity of porcupine’s species (Coendou spp.) in the country. We introduced the first record of one species (Coendou ichillus) from the Orinoco river basin of the country, extending the distribution of the species by more than 600 km to the north from confirmed localities in Ecuador and Peru. Additionally, we presented new records of two species from different natural regions than previously known. In a similar analysis , we reviewed specimens of acouchis (Myoprocta spp.) and confirmed the presence of two taxa occupying common areas in Colombian Amazon, even though checklists assumed geographic isolation between species. Apparently, previous hypotheses concerning the distribution of these species were based on inadequate revision of specimens in natural collections.
Thanks to the big efforts of different researchers, the number of registered species of native mammals from Colombia over the last fifteen years (2000-2015) has increased in forty seven. Most of the additions (17) correspond to bats (order Chiroptera), one of the most studied group in the country. Nevertheless, the increasing number of mammal diversity is not only restricted to small or cryptic mammal species. This is reflected by the discovery of species of “charismatic groups” such as primates (2), carnivores (1), and tapirs (1). One analysis carried out by Ceballos & Ehrlich (2009) estimated that around 40% of the 408 new mammal species described worldwide between 1993 and 2008 were not formerly included within another species (e.g. synonyms or subspecies). In many cases, described species are highly distinctive and belong to relatively large and conspicuous groups (primates, ungulates, cetaceans).
Although Colombia is one of the global hotspots for mammalian diversity, little or nothing is known about diversity or distributional patterns of certain species, especially the endemic taxa, and collected data is biased towards the most populated regions. Using a very good example, Diego Lizcano – a Colombian biologist expert in mammal ecology and conservation– carried out basic analyses of mammal datasets using R to understand how much Colombia knows about its biodiversity. Clearly, the presence of the main cities and roads in the Andes have allowed for higher levels of sampling effort in this region. In contrast, the Amazonia, which is considered one of the biggest biodiversity hotspots, is the least sampled region. As we confirmed with our examples of medium size rodents, and recent records of bats (Suárez-Castro et al. 2012, Morales-Martínez and Suárez-Castro 2014), biotas of some relatively expansive areas remain largely unexplored and unsurveyed.
Even though many researchers assume that mammals constitute a well-known group, a comprehensive understanding of mammalian diversity remains a distant goal (Reeder et al. 2007, Ceballos and Erich 2009) Unfortunately, despite the role of biological specimens as source of data for different studies (Patterson 2002), some national laws, as well as groups leading rapid environmental impact assessments seem to discourage scientific collection of specimens. Furthermore, scientific interest and investment in taxonomy appear to be diminishing (Hutchings 2010, Wägele et al. 2011). Some claims that most discoveries have already been made and placed in museums are adding more confusion to the debate . By ignoring the importance of intensive fieldwork and the review of museum specimens, we are not only providing bad quality information to decision makers, but discarding the opportunity to obtain morphological and molecular information to understand basic aspects on taxonomy, intraspecific variation, and species distribution patterns that remain largely unresolved.
Ceballos, G. and Ehrlich, P. R. 2009. Discoveries of new mammal species and their implications for conservation and ecosystem services. Proceedings of the National Academy of Sciences 106, 3841-3846.
Hutchings, P. 2010. Why are taxonomists often regarded as second class citizens? a misclassification that threatens the basic infrastructure of biodiversity Australian Museum, 6, College Street, Sydney NSW
Morales-Martínez, D.M. and Suárez-Castro, A.F. 2014. New records for Glyphonycteris Thomas, 1896 (Chiroptera: Phyllostomidae) from Colombia. Checklist DOI: http://dx.doi.org/10.15560/10.3.639
Patterson, B. D. 2002. On the continuing need for scientific collecting of mammals. J. Neotrop. Mammal: 9:253-262.
Ramírez-Chaves, H. E., Suárez-Castro, A. F., Morales-Martínez, D, M., and Vallejo-Pareja, M. C. Richness and distribution of porcupines (Erethizontidae: Coendou) from Colombia. Mammalia. DOI: 10.1515/mammalia-2014-0158
Ramírez-Chaves, H. E., Suárez-Castro, A. F. and Patterson, B. D. 2014. Re-examining the hypothesis of allopatric distribution of Myoprocta acouchy and M. pratti (Mammalia: Dasyproctidae) in South America. Papéis Avulsos de Zoologia 54(31): 447-456.
Reeder D.M., Helgen, K.M and Wilson, D.E. 2007. Global Trends and Biases in New Mammal Species Discoveries. Occasional Papers Museum of Texas Tech University. 269: 1-35
Suárez-Castro, A.F., Ramírez-Chaves, H., Rodriguez-Posada, M. and García, J. 2012 New records of Peropteryx leucoptera and first record of Peropteryx pallidoptera (Chiroptera-Emballonuridae) from Colombia.
Mastozoología Neotropical 19: 165-171
Wägele, H., Klussmann-Kolb, A., Kuhlmann, M., Haszprunar, G., Lindberg, D., Koch, A. and Wolfgang Wägele, J. The taxonomist – an endangered race. A practical proposal for its survival. Frontiers in Zoology 2011, 8:25