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taxadb

R build status lifecycle Coverage status CRAN status DOI

The goal of taxadb is to provide fast, consistent access to taxonomic data, supporting common tasks such as resolving taxonomic names to identifiers, looking up higher classification ranks of given species, or returning a list of all species below a given rank. These tasks are particularly common when synthesizing data across large species assemblies, such as combining occurrence records with trait records.

Existing approaches to these problems typically rely on web APIs, which can make them impractical for work with large numbers of species or in more complex pipelines. Queries and returned formats also differ across the different taxonomic authorities, making tasks that query multiple authorities particularly complex. taxadb creates a local database of most readily available taxonomic authorities, each of which is transformed into consistent, standard, and researcher-friendly tabular formats.

Install and initial setup

To get started, install from CRAN

install.pacakges("taxadb")

or install the development version directly from GitHub:

devtools::install_github("ropensci/taxadb")
library(taxadb)
library(dplyr) # Used to illustrate how a typical workflow combines nicely with `dplyr`

Create a local copy of the Catalogue of Life (2018) database:

td_create("col", overwrite=FALSE)

Read in the species list used by the Breeding Bird Survey:

bbs_species_list <- system.file("extdata/bbs.tsv", package="taxadb")
bbs <- read.delim(bbs_species_list)

Getting names and ids

Two core functions are get_ids() and get_names(). These functions take a vector of names or ids (respectively), and return a vector of ids or names (respectively). For instance, we can use this to attempt to resolve all the bird names in the Breeding Bird Survey against the Catalogue of Life:

birds <- bbs %>% 
  select(species) %>% 
  mutate(id = taxalight::get_ids(species, "col"))

head(birds, 10)
#>                          species          id
#> 1         Dendrocygna autumnalis COL:3177882
#> 2            Dendrocygna bicolor COL:3177881
#> 3                Anser canagicus COL:3178026
#> 4             Anser caerulescens COL:3178024
#> 5  Chen caerulescens (blue form)        <NA>
#> 6                   Anser rossii COL:3178025
#> 7                Anser albifrons COL:3178017
#> 8                Branta bernicla COL:3178037
#> 9      Branta bernicla nigricans COL:3185200
#> 10             Branta hutchinsii COL:3178039

Note that some names cannot be resolved to an identifier. This can occur because of miss-spellings, non-standard formatting, or the use of a synonym not recognized by the naming provider. Names that cannot be uniquely resolved because they are known synonyms of multiple different species will also return NA. The filter_name filtering functions can help us resolve this last case (see below).

get_ids() returns the IDs of accepted names, that is dwc:AcceptedNameUsageIDs. We can resolve the IDs into accepted names:

birds %>% 
  mutate(accepted_name = get_names(id, "col")) %>% 
  head()
#>                         species          id          accepted_name
#> 1        Dendrocygna autumnalis COL:3177882 Dendrocygna autumnalis
#> 2           Dendrocygna bicolor COL:3177881    Dendrocygna bicolor
#> 3               Anser canagicus COL:3178026          Chen canagica
#> 4            Anser caerulescens COL:3178024      Chen caerulescens
#> 5 Chen caerulescens (blue form)        <NA>                   <NA>
#> 6                  Anser rossii COL:3178025            Chen rossii

This illustrates that some of our names, e.g. Dendrocygna bicolor are accepted in the Catalogue of Life, while others, Anser canagicus are known synonyms of a different accepted name: Chen canagica. Resolving synonyms and accepted names to identifiers helps us avoid the possible miss-matches we could have when the same species is known by two different names.

Taxonomic Data Tables

Local access to taxonomic data tables lets us do much more than look up names and ids. A family of filter_* functions in taxadb help us work directly with subsets of the taxonomic data. As we noted above, this can be useful in resolving certain ambiguous names.

For instance, Trochalopteron henrici gucenense does not resolve to an identifier in ITIS:

get_ids("Trochalopteron henrici gucenense") 
#> [1] NA

Using filter_name(), we find this is because the name resolves not to zero matches, but to more than one match:

filter_name("Trochalopteron henrici gucenense") 
#> # A tibble: 2 x 17
#>    sort taxonID   scientificName      taxonRank acceptedNameUsa… taxonomicStatus
#>   <int> <chr>     <chr>               <chr>     <chr>            <chr>          
#> 1     1 ITIS:924… Trochalopteron hen… subspeci… ITIS:916116      synonym        
#> 2     1 ITIS:924… Trochalopteron hen… subspeci… ITIS:916117      synonym        
#> # … with 11 more variables: update_date <chr>, kingdom <chr>, phylum <chr>,
#> #   class <chr>, order <chr>, family <chr>, genus <chr>, specificEpithet <chr>,
#> #   infraspecificEpithet <chr>, vernacularName <chr>, input <chr>
filter_name("Trochalopteron henrici gucenense")  %>%
  mutate(acceptedNameUsage = get_names(acceptedNameUsageID)) %>% 
  select(scientificName, taxonomicStatus, acceptedNameUsage, acceptedNameUsageID)
#> # A tibble: 2 x 4
#>   scientificName          taxonomicStatus acceptedNameUsage    acceptedNameUsag…
#>   <chr>                   <chr>           <chr>                <chr>            
#> 1 Trochalopteron henrici… synonym         Trochalopteron elli… ITIS:916116      
#> 2 Trochalopteron henrici… synonym         Trochalopteron henr… ITIS:916117

Similar functions filter_id, filter_rank, and filter_common take IDs, scientific ranks, or common names, respectively. Here, we can get taxonomic data on all bird names in the Catalogue of Life:

filter_rank(name = "Aves", rank = "class", provider = "col")
#> # A tibble: 36,336 x 21
#>     sort taxonID   scientificName    acceptedNameUsag… taxonomicStatus taxonRank
#>    <int> <chr>     <chr>             <chr>             <chr>           <chr>    
#>  1     1 COL:3148… Nisaetus nanus    COL:3148416       accepted        species  
#>  2     1 COL:3148… Circaetus beaudo… COL:3148666       accepted        species  
#>  3     1 COL:3148… Cariama cristata  COL:3148731       accepted        species  
#>  4     1 COL:3148… Chunga burmeiste… COL:3148732       accepted        species  
#>  5     1 COL:3148… Eurypyga helias   COL:3148733       accepted        species  
#>  6     1 COL:3148… Rhynochetos juba… COL:3148734       accepted        species  
#>  7     1 COL:3148… Leptosomus disco… COL:3148735       accepted        species  
#>  8     1 COL:3148… Neotis heuglinii  COL:3148736       accepted        species  
#>  9     1 COL:3148… Neotis ludwigii   COL:3148737       accepted        species  
#> 10     1 COL:3148… Neotis denhami    COL:3148738       accepted        species  
#> # … with 36,326 more rows, and 15 more variables: kingdom <chr>, phylum <chr>,
#> #   class <chr>, order <chr>, family <chr>, genus <chr>, specificEpithet <chr>,
#> #   infraspecificEpithet <chr>, taxonConceptID <chr>, isExtinct <chr>,
#> #   nameAccordingTo <chr>, namePublishedIn <chr>,
#> #   scientificNameAuthorship <chr>, vernacularName <chr>, input <chr>

Combining these with dplyr functions can make it easy to explore this data: for instance, which families have the most species?

filter_rank(name = "Aves", rank = "class", provider = "col") %>%
  filter(taxonomicStatus == "accepted", taxonRank=="species") %>% 
  group_by(family) %>%
  count(sort = TRUE) %>% 
  head()
#> # A tibble: 6 x 2
#> # Groups:   family [6]
#>   family           n
#>   <chr>        <int>
#> 1 Tyrannidae     401
#> 2 Thraupidae     374
#> 3 Psittacidae    370
#> 4 Columbidae     344
#> 5 Trochilidae    338
#> 6 Muscicapidae   314

Using the database connection directly

filter_* functions by default return in-memory data frames. Because they are filtering functions, they return a subset of the full data which matches a given query (names, ids, ranks, etc), so the returned data.frames are smaller than the full record of a naming provider. Working directly with the SQL connection to the MonetDBLite database gives us access to all the data. The taxa_tbl() function provides this connection:

taxa_tbl("col")
#> # Source:   table<2020_dwc_col> [?? x 19]
#> # Database: duckdb_connection
#>    taxonID  scientificName    acceptedNameUsa… taxonomicStatus taxonRank kingdom
#>    <chr>    <chr>             <chr>            <chr>           <chr>     <chr>  
#>  1 COL:3738 Lobesia triacant… COL:3738         accepted        species   Animal…
#>  2 COL:4116 Syncollesis tril… COL:4116         accepted        species   Animal…
#>  3 COL:4118 Anisodes anablem… COL:4118         accepted        species   Animal…
#>  4 COL:4122 Cyclophora carol… COL:4122         accepted        species   Animal…
#>  5 COL:4127 Morchella magnis… COL:4127         accepted        species   Fungi  
#>  6 COL:4128 Streptothrix eff… COL:4128         accepted        species   Fungi  
#>  7 COL:4344 Aplosporella fau… COL:4344         accepted        species   Fungi  
#>  8 COL:9466 Synalus angustus  COL:9466         accepted        species   Animal…
#>  9 COL:9467 Synalus terrosus  COL:9467         accepted        species   Animal…
#> 10 COL:9468 Synema spinosum   COL:9468         accepted        species   Animal…
#> # … with more rows, and 13 more variables: phylum <chr>, class <chr>,
#> #   order <chr>, family <chr>, genus <chr>, specificEpithet <chr>,
#> #   infraspecificEpithet <chr>, taxonConceptID <chr>, isExtinct <chr>,
#> #   nameAccordingTo <chr>, namePublishedIn <chr>,
#> #   scientificNameAuthorship <chr>, vernacularName <chr>

We can still use most familiar dplyr verbs to perform common tasks. For instance: which species has the most known synonyms?

taxa_tbl("col") %>% 
  count(acceptedNameUsageID, sort=TRUE)
#> # Source:     lazy query [?? x 2]
#> # Database:   duckdb_connection
#> # Ordered by: desc(n)
#>    acceptedNameUsageID     n
#>    <chr>               <dbl>
#>  1 COL:274062            456
#>  2 COL:353741            373
#>  3 COL:3778950           329
#>  4 COL:2535424           328
#>  5 COL:2921616           322
#>  6 COL:2532677           307
#>  7 COL:3779182           302
#>  8 COL:353740            296
#>  9 COL:2531203           253
#> 10 COL:1585420           252
#> # … with more rows

However, unlike the filter_* functions which return convenient in-memory tables, this is still a remote connection. This means that direct access using the taxa_tbl() function (or directly accessing the database connection using td_connect()) is more low-level and requires greater care. For instance, we cannot just add a %>% mutate(acceptedNameUsage = get_names(acceptedNameUsageID)) to the above, because get_names does not work on a remote collection. Instead, we would first need to use a collect() to pull the summary table into memory. Users familiar with remote databases in dplyr will find using taxa_tbl() directly to be convenient and fast, while other users may find the filter_* approach to be more intuitive.

Learn more

  • See richer examples the package Tutorial.

  • Learn about the underlying data sources and formats in Data Sources

  • Get better performance by selecting an alternative database backend engines.


Please note that this project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms.

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