Showing posts with label OBIS. Show all posts
Showing posts with label OBIS. Show all posts

Thursday, August 18, 2016

GBIF Challenge: €31,000 in prizes for analysing and addressing gaps and biases in primary biodiversity data

Full widthIn a classic paper Boggs (1949) appealed for an “atlas of ignorance”, an honest assessment of what we know we don’t know:

Boggs, S. W.. (1949). An Atlas of Ignorance: A Needed Stimulus to Honest Thinking and Hard Work. Proceedings of the American Philosophical Society, 93(3), 253–258. Retrieved from http://www.jstor.org/stable/3143475

This is the theme of this year's GBIF Challenge: Analysing and addressing gaps and biases in primary biodiversity data. "Gaps" can be gaps in geographic coverage, taxa group, or types of data. GBIF is looking for ways to access the nature of the gaps in the data it is aggregating from its network of contributors.

How to enter

Details on how to enter are on the Challenge website, deadline is September 30th.

Ideas

One approach to gap analysis is to compare what we expect to see with what we actually have. For example, we might take a “well-known” group of organisms and use that to benchmark GBIF’s data coverage. A drawback is that the “well-known” organisms tend to be the usual suspects (birds, mammals, fish, etc.), and there is the issue of whether the chosen group is a useful proxy for other taxa. Another approach is to base the estimate of ignorance on the data itself. For example, OBIS has computed Hurlbert's index of biodiversity for its database, e.g. http://data.unep-wcmc.org/datasets/16 Screenshot 2016 08 18 15 13 59 Can we scale these methods to the 600+ million records in GBIF? There are some clever methods for using resampling methods (such as the bootstrap) on large data sets that might be relevant, see http://www.unofficialgoogledatascience.com/2015/08/an-introduction-to-poisson-bootstrap_26.html.

Another approach might be to compare different datasets for the same taxa, particularly if one data set is not in GBIF. Or perhaps we can compare datasets for the same taxa collected by different methods.

Or we could look at taxonomic gaps. In an earlier post The Zika virus, GBIF, and the missing mosquitoes I noted that GBIF's coverage of vectors of the Zika virus was very poor. How well does GBIF cover vectors and other organisms relevant to human health? Maybe we could generalise this to explore other taxa. It might, for example, be interesting to compare degree of coverage for a species with some measure of the "importance" of that species. Measures of importance could be based on, say, number of hits in Google Scholar for that species, size of Wikipedia page (see Wikipedia mammals and the power law), etc.

Gaps might also be gaps in data completeness, quality, or type.

Summary

This post has barely scratched the surface of what is possible. But I think one important thing to bear in mind is that the best analyses of gaps are those that lead to "actionable insights", in other words, if you are going to enter the challenge (and please do, it's free to enter and there's money to be won), how does you entry help GBIF and the wider biodiversity community decide what to do about gaps?

Tuesday, December 01, 2015

Guest post: 10 years of global biodiversity databases: are we there yet?

YtNkVT2UThis guest post by Tony Rees explores some of the themes from his recent talk 10 years of Global Biodiversity Databases: Are We There Yet?.

A couple of months ago I received an invitation to address the upcoming 2015 meeting of the Malacological Society of Australasia (Australian and New Zealand mollusc persons for the uninitiated) on some topic associated with biodiversity databases, and I decided that a decadal review might be an interesting exercise, both for my potential audience (perhaps) and for my own interest (definitely). Well, the talk is delivered and the slides are available on the web for viewing if interested, and Rod has kindly invited me to present some of its findings here, and possibly stimulate some ongoing discussion since a lot of my interests overlap his own quite closely. I was also somewhat influenced in my choice of title by a previous presentation of Rod's from some 5 years back, "Why aren't we there yet?" which provides a slightly pessimistic counterpoint to my own perhaps more optimistic summary.

I decided to construct the talk around 5 areas: compilations of taxonomic names and associated valid/accepted taxa; links to the literature (original citations, descriptions, more); machine-addressable lists of taxon traits; compilations of georeferenced species data points such as OBIS and GBIF; and synoptic efforts in the environmental niche modelling area (all or many species so as to be able to produce global biodiversity as well as single-species maps). Without recapping the entire content of my talk (which you can find on SlideShare), I thought I would share with readers of this blog some of the more interesting conclusions, many of which are not readily available elsewhere, at least not with effort to chase down and/or make educated guesses.

In the area of taxonomic names, for animals (sensu lato) ION has gone up from 1.8m to 5.2m names (2.8m to 3.5m indexed documents) from all ranks (synonyms not distinguished) over the cited period 2005-2015, while Catalogue of Life has gone up from 0.5m species names + ?? synonyms to 1.6m species names + 1.3m synonyms over the same period; for fossils, BioNames database is making some progress in linking ION names to external resources on the web but, at less than 100k such links, is still relatively small scale and without more than a single-operator level of resourcing. A couple of other "open access" biological literature indexing activities are still at a modest level (e.g. 250k-350k citations, as against an estimated biological literature of perhaps 20m items) at present, and showing few signs of current active development (unless I have missed them of course).

Comprehensive databases of taxon traits (in machine addressable form) appear to have started with the author’s own "IRMNG" genus- and species- level compendium which was initially tailored to OBIS needs for simply differentiating organisms into extant vs. fossil, marine vs. nonmarine. More comprehensive indexes exist for specific groups and recently, Encyclopedia of Life has established "TraitBank" which is making some headway although some of the "traits" such as geographic distribution (a bounding box from either GBIF or OBIS) and "number of GenBank sequences" stretch the concept of trait a little (just my two cents' worth, of course), and the newly created linkage to Google searches is to be applauded.

With regard to aggregating georeferenced species data (specimens and observations), both OBIS (marine taxa only) and GBIF (all taxa) have made quite a lot of progress over the past ten years, OBIS increasing its data holdings ninefold from 5.6m to 44.9m (from 38 to 1,900+ data providers) and GBIF more than tenfold from 45m to 577m records over the same period, from 300+ to over 15k providers. While these figures look healthy there are still many data gaps in holdings e.g. by location sampled, year/season, ocean depth, distance to land etc. and it is probably a fair question to ask what is the real "end point" for such projects, i.e. somewhere between "a record for every species" and "a record for every individual of every species", perhaps...

Global / synoptic niche modelling projects known to the author basically comprise Lifemapper for terrestrial species and AquaMaps for marine taxa (plus some freshwater). Lifemapper claims "data for over 100,000 species" but it is unclear whether this corresponds to the number of completed range maps available at this time, while AquaMaps has maps for over 22,000 species (fishes, marine mammals and invertebrates, with an emphasis on fishes) each of which has a point data map, a native range map clipped to where the species is believed to occur, an "all suitable habitat map" (the same unclipped) and a "year 2100 map" showing projected range changes under one global warming scenario. Mapping parameters can also be adjusted by the user using an interactive "create your own map" function, and stacking all completed maps together produces plots of computed ocean biodiversity plus the ability to undertake web-based "what [probably] lives here" queries for either all species or for particular groups. Between these two projects (which admittedly use different modelling methodologies but both should produce useful results as a first pass) the state of synoptic taxon modelling actually appears quite good, especially since there are ongoing workshops e.g. the recent AMNH/GBIF workshop Biodiversity Informatics and Modelling Species Distributions at which further progress and stumbling blocks can be discussed.

So, some questions arising:

  • Who might produce the best "single source" compendium of expert-reviewed species lists, for all taxa, extant and fossil, and how might this happen (my guess: a consortium of Catalogue of Life + PaleoBioDB at some future point)
  • Will this contain links to the literature, at least citations but preferably as online digital documents where available? (CoL presently no, PaleoBioDB has human-readable citations only at present)
  • Will EOL increasingly claim the "TraitBank" space, and do a good enough job of it? (also bearing in mind that EOL is still an aggregator, not an original content creator, i.e. somebody still has to create it elsewhere)
  • Will OBIS and/or GBIF ever be "complete", and how will we know when we’ve got there (or, how complete is enough for what users might require)?
  • Same for niche modelling/predicted species maps: will all taxa eventually be covered, and will the results be (generally) reliable and useable (and at what scale); or, what more needs to be done to increase map quality and reliability.

Opinions, other insights welcome!

Monday, October 06, 2008

Global biogeographical data bases on marine fishes: caveat emptor

D. Ross Robertson has published a paper entitled "Global biogeographical data bases on marine fishes: caveat emptor" (doi:10.1111/j.1472-4642.2008.00519.x - DOI is broken, you can get the article here). The paper concludes:
Any biogeographical analysis of fish distributions that uses GIS data on marine fishes provided by FishBase and OBIS 'as is' will be seriously compromised by the high incidence of species with large-scale geographical errors. A major revision of GIS data for (at least) marine fishes provided by FishBase, OBIS, GBIF and EoL is essential. While the primary sources naturally bear responsibility for data quality, global online providers of aggregated data are also responsible for the content they serve, and cannot side-step the issue by simply including generalized disclaimers about data quality. Those providers need to actively coordinate, organize and effect a revision of GIS data they serve, as revisions by individual users will inevitably lead to confused science (which version did you use?) and a tremendous expenditure of redundant effort. To begin with, it should be relatively easy for providers to segregate all data on pelagic larvae and adults of marine organisms that they serve online. Providers should also include the capacity for users to post readily accessible public comments about the accuracy of individual records and the overall quality of individual data bases. This would stimulate improvements in data quality, and generate 'selection pressures' favouring the usage of better quality data bases, and the revision or elimination of poor-quality data bases. The services provided to the global science community by the interlinked group of online providers of biodiversity data are invaluable and should not be allowed to be discredited by a high incidence of known serious errors in GIS data among marine fishes, and, likely, other marine organisms. (emphasis added)

As I've noted elsewhere on this blog, and as demonstrated by Yesson et al.'s paper on legume records in GBIF (doi:10.1371/journal.pone.0001124) (not cited by Robertson), there are major problems with geographical information in public databases. I suspect there will be more papers like this, which I hope will inspire database providers and aggregators to take the issue seriously. (Thanks to David Patterson for spotting this paper).