taxize vignette - a taxonomic toolbelt for R

taxize is a taxonomic toolbelt for R. taxize wraps APIs for a large suite of taxonomic databases availab on the web.

Installation

First, install and load taxize into the R session.

install.packages("taxize")
library("taxize")

Advanced users can also download and install the latest development copy from GitHub.

Resolve taxonomic name

This is a common task in biology. We often have a list of species names and we want to know a) if we have the most up to date names, b) if our names are spelled correctly, and c) the scientific name for a common name. One way to resolve names is via the Global Names Resolver (GNR) service provided by the Encyclopedia of Life. Here, we are searching for two misspelled names:

temp <- gnr_resolve(names = c("Helianthos annus", "Homo saapiens"))
head( temp$results )
#>     submitted_name         matched_name data_source_title score
#> 1 Helianthos annus     Helianthus annus               EOL  0.75
#> 2 Helianthos annus  Helianthus annus L.               EOL  0.75
#> 3 Helianthos annus     Helianthus annus     uBio NameBank  0.75
#> 4 Helianthos annus Helianthus annuus L. Catalogue of Life  0.75
#> 5 Helianthos annus Helianthus annuus L.              ITIS  0.75
#> 6 Helianthos annus    Helianthus annuus              NCBI  0.75

The correct spellings are Helianthus annuus and Homo sapiens. Another approach uses the Taxonomic Name Resolution Service via the Taxosaurus API developed by iPLant and the Phylotastic organization. In this example, we provide a list of species names, some of which are misspelled, and we'll call the API with the tnrs function.

mynames <- c("Helianthus annuus", "Pinus contort", "Poa anua", "Abis magnifica",
    "Rosa california", "Festuca arundinace", "Sorbus occidentalos","Madia sateva")
tnrs(query = mynames, source = "iPlant_TNRS")[ , -c(5:7)]
#> Calling http://taxosaurus.org/retrieve/f2be9ae38992ada133d90edd3a5e6322
#>         submittedname        acceptedname    sourceid score
#> 1 Sorbus occidentalos Sorbus occidentalis iPlant_TNRS  0.99
#> 2  Festuca arundinace Festuca arundinacea iPlant_TNRS  0.99
#> 3      Abis magnifica     Abies magnifica iPlant_TNRS  0.96
#> 4       Pinus contort      Pinus contorta iPlant_TNRS  0.98
#> 5            Poa anua           Poa annua iPlant_TNRS  0.96
#> 6        Madia sateva        Madia sativa iPlant_TNRS  0.97
#> 7   Helianthus annuus   Helianthus annuus iPlant_TNRS     1
#> 8     Rosa california    Rosa californica iPlant_TNRS  0.99

It turns out there are a few corrections: e.g., Madia sateva should be Madia sativa, and Rosa california should be Rosa californica. Note that this search worked because fuzzy matching was employed to retrieve names that were close, but not exact matches. Fuzzy matching is only available for plants in the TNRS service, so we advise using EOL's Global Names Resolver if you need to resolve animal names.

taxize takes the approach that the user should be able to make decisions about what resource to trust, rather than making the decision. Both the EOL GNR and the TNRS services provide data from a variety of data sources. The user may trust a specific data source, thus may want to use the names from that data source. In the future, we may provide the ability for taxize to suggest the best match from a variety of sources.

Another common use case is when there are many synonyms for a species. In this example, we have three synonyms of the currently accepted name for a species.

mynames <- c("Helianthus annuus ssp. jaegeri", "Helianthus annuus ssp. lenticularis", "Helianthus annuus ssp. texanus")
(tsn <- get_tsn(mynames, accepted = FALSE))
[1] "525928" "525929" "525930"
attr(,"match")
[1] "found" "found" "found"
attr(,"uri")
[1] "http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=525928"
[2] "http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=525929"
[3] "http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=525930"
attr(,"class")
[1] "tsn"
library("plyr")
ldply(tsn, itis_acceptname)
  submittedtsn      acceptedname acceptedtsn
1       525928 Helianthus annuus       36616
2       525929 Helianthus annuus       36616
3       525930 Helianthus annuus       36616

Retrieve higher taxonomic names

Another task biologists often face is getting higher taxonomic names for a taxa list. Having the higher taxonomy allows you to put into context the relationships of your species list. For example, you may find out that species A and species B are in Family C, which may lead to some interesting insight, as opposed to not knowing that Species A and B are closely related. This also makes it easy to aggregate/standardize data to a specific taxonomic level (e.g., family level) or to match data to other databases with different taxonomic resolution (e.g., trait databases).

A number of data sources in taxize provide the capability to retrieve higher taxonomic names, but we will highlight two of the more useful ones: Integrated Taxonomic Information System (ITIS) and National Center for Biotechnology Information (NCBI). First, we'll search for two species, Abies procera} and *Pinus contorta within ITIS.

specieslist <- c("Abies procera","Pinus contorta")
classification(specieslist, db = 'itis')
#> 
#> Retrieving data for taxon 'Abies procera'
#> 
#> 
#> Retrieving data for taxon 'Pinus contorta'
#> $`Abies procera`
#>               name          rank     id
#> 1          Plantae       Kingdom 202422
#> 2   Viridaeplantae    Subkingdom 846492
#> 3     Streptophyta  Infrakingdom 846494
#> 4     Tracheophyta      Division 846496
#> 5  Spermatophytina   Subdivision 846504
#> 6     Gymnospermae Infradivision 846506
#> 7        Pinopsida         Class 500009
#> 8          Pinales         Order 500028
#> 9         Pinaceae        Family  18030
#> 10           Abies         Genus  18031
#> 11   Abies procera       Species 181835
#> 
#> $`Pinus contorta`
#>               name          rank     id
#> 1          Plantae       Kingdom 202422
#> 2   Viridaeplantae    Subkingdom 846492
#> 3     Streptophyta  Infrakingdom 846494
#> 4     Tracheophyta      Division 846496
#> 5  Spermatophytina   Subdivision 846504
#> 6     Gymnospermae Infradivision 846506
#> 7        Pinopsida         Class 500009
#> 8          Pinales         Order 500028
#> 9         Pinaceae        Family  18030
#> 10           Pinus         Genus  18035
#> 11  Pinus contorta       Species 183327
#> 
#> attr(,"class")
#> [1] "classification"
#> attr(,"db")
#> [1] "itis"

It turns out both species are in the family Pinaceae. You can also get this type of information from the NCBI by doing classification(specieslist, db = 'ncbi').

Instead of a full classification, you may only want a single name, say a family name for your species of interest. The function *tax_name} is built just for this purpose. As with the classification function you can specify the data source with the db argument, either ITIS or NCBI.

tax_name(query = "Helianthus annuus", get = "family", db = "ncbi")
#> 
#> Retrieving data for taxon 'Helianthus annuus'
#>     db             query     family
#> 1 ncbi Helianthus annuus Asteraceae

I may happen that a data source does not provide information on the queried species, than one could take the result from another source and union the results from the different sources.

Interactive name selection

As mentioned most databases use a numeric code to reference a species. A general workflow in taxize is: Retrieve Code for the queried species and then use this code to query more data/information.

Below are a few examples. When you run these examples in R, you are presented with a command prompt asking for the row that contains the name you would like back; that output is not printed below for brevity. In this example, the search term has many matches. The function returns a data frame of the matches, and asks for the user to input what row number to accept.

get_uid(sciname = "Pinus")
#> 
#> Retrieving data for taxon 'Pinus'
#> 
#> 
#> 
#> 
#> 
#> More than one UID found for taxon 'Pinus'!
#> 
#>             Enter rownumber of taxon (other inputs will return 'NA'):
#>      UID     Rank    Division
#> 1 139271 subgenus seed plants
#> 2   3337    genus seed plants
#> Input accepted, took UID '139271'.
#> [1] "139271"
#> attr(,"class")
#> [1] "uid"
#> attr(,"match")
#> [1] "found"
#> attr(,"uri")
#> [1] "http://www.ncbi.nlm.nih.gov/taxonomy/139271"

In another example, you can pass in a long character vector of taxonomic names (although this one is rather short for demo purposes):

splist <- c("annona cherimola", 'annona muricata', "quercus robur")
get_tsn(searchterm = splist, searchtype = "scientific")
#> 
#> Retrieving data for taxon 'annona cherimola'
#> 
#> 
#> Retrieving data for taxon 'annona muricata'
#> 
#> 
#> Retrieving data for taxon 'quercus robur'
#> [1] "506198" "18098"  "19405" 
#> attr(,"match")
#> [1] "found" "found" "found"
#> attr(,"uri")
#> [1] "http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=506198"
#> [2] "http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=18098" 
#> [3] "http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=19405" 
#> attr(,"class")
#> [1] "tsn"

There are functions for many other sources

Sometimes with these functions you get a lot of data back. In these cases you may want to limit your choices. Soon we will incorporate the ability to filter using regex to limit matches, but for now, we have a new parameter, rows, which lets you select certain rows. For example, you can select the first row of each given name, which means there is no interactive component:

get_nbnid(c("Zootoca vivipara","Pinus contorta"), rows = 1)
#> 
#> Retrieving data for taxon 'Zootoca vivipara'
#> 
#> 
#> Retrieving data for taxon 'Pinus contorta'
#> [1] "NHMSYS0001706186" "NHMSYS0000494848"
#> attr(,"class")
#> [1] "nbnid"
#> attr(,"match")
#> [1] "found" "found"
#> attr(,"uri")
#> [1] "https://data.nbn.org.uk/Taxa/NHMSYS0001706186"
#> [2] "https://data.nbn.org.uk/Taxa/NHMSYS0000494848"

Or you can select a range of rows

get_nbnid(c("Zootoca vivipara","Pinus contorta"), rows = 1:3)
#> 
#> Retrieving data for taxon 'Zootoca vivipara'
#> 
#> 
#> 
#> 
#> 
#> More than one nbnid found for taxon 'Zootoca vivipara'!
#> 
#>             Enter rownumber of taxon (other inputs will return 'NA'):
#>              nbnid                  searchMatchTitle       rank
#> 1 NHMSYS0001706186                  Zootoca vivipara    Species
#> 2 NHMSYS0020784960 Zootoca vivipara subsp. pannonica Subspecies
#> 3 NHMSYS0001706185                           Zootoca      Genus
#>    nameStatus
#> 1 Recommended
#> 2 Recommended
#> 3 Recommended
#> Input accepted, took nbnid 'NHMSYS0001706186'.
#> 
#> 
#> Retrieving data for taxon 'Pinus contorta'
#> 
#> 
#> 
#> 
#> 
#> More than one nbnid found for taxon 'Pinus contorta'!
#> 
#>             Enter rownumber of taxon (other inputs will return 'NA'):
#>              nbnid               searchMatchTitle       rank  nameStatus
#> 1 NHMSYS0000494848   Pinus contorta var. contorta    Variety Recommended
#> 2 NBNSYS0000004786                 Pinus contorta    Species Recommended
#> 3 NHMSYS0000494848 Pinus contorta subsp. contorta Subspecies Recommended
#> Input accepted, took nbnid 'NHMSYS0000494848'.
#> [1] "NHMSYS0001706186" "NHMSYS0000494848"
#> attr(,"class")
#> [1] "nbnid"
#> attr(,"match")
#> [1] "found" "found"
#> attr(,"uri")
#> [1] "https://data.nbn.org.uk/Taxa/NHMSYS0001706186"
#> [2] "https://data.nbn.org.uk/Taxa/NHMSYS0000494848"

In addition, in case you don't want to do interactive name selection in the case where there are a lot of names, you can get all data back with functions of the form, e.g., get_tsn_(), and likewise for other data sources. For example:

out <- get_nbnid_("Poa annua")
#> 
#> Retrieving data for taxon 'Poa annua'
NROW(out)
#> [1] 1

That's a lot of data, so we can get only certain rows back

get_nbnid_("Poa annua", rows = 1:10)
#> 
#> Retrieving data for taxon 'Poa annua'
#> $`Poa annua`
#>    ptaxonVersionKey searchMatchTitle    rank   nameStatus
#> 1  NBNSYS0000002544        Poa annua Species  Recommended
#> 2  NHMSYS0000461798              Poa   Genus  Recommended
#> 3  NHMSYS0000461804         Poa laxa Species      Synonym
#> 4  NHMSYS0021060390           Poales   Order  Recommended
#> 5  NBNSYS0000002551       Poa glauca Species  Recommended
#> 6  NBNSYS0000002547       Poa alpina Species  Recommended
#> 7  NHMSYS0000456981       Poa rigida Species      Synonym
#> 8  NBNSYS0000002545       Poa exilis Species Undetermined
#> 9  NBNSYS0000002551       Poa caesia Species      Synonym
#> 10 NBNSYS0000160753          Poaceae  Family  Recommended

Coerce numerics/alphanumerics to taxon IDs

We've also introduced in v0.5 the ability to coerce numerics and alphanumerics to taxonomic ID classes that are usually only retrieved via get_*() functions.

For example, adfafd

as.gbifid(get_gbifid("Poa annua")) # already a uid, returns the same
#> 
#> Retrieving data for taxon 'Poa annua'
#> [1] "2704179"
#> attr(,"class")
#> [1] "gbifid"
#> attr(,"match")
#> [1] "found"
#> attr(,"uri")
#> [1] "http://www.gbif.org/species/2704179"
as.gbifid(2704179) # numeric
#> [1] "2704179"
#> attr(,"class")
#> [1] "gbifid"
#> attr(,"match")
#> [1] "found"
#> attr(,"uri")
#> [1] "http://www.gbif.org/species/2704179"
as.gbifid("2704179") # character
#> [1] "2704179"
#> attr(,"class")
#> [1] "gbifid"
#> attr(,"match")
#> [1] "found"
#> attr(,"uri")
#> [1] "http://www.gbif.org/species/2704179"
as.gbifid(list("2704179","2435099","3171445")) # list, either numeric or character
#> [1] "2704179" "2435099" "3171445"
#> attr(,"class")
#> [1] "gbifid"
#> attr(,"match")
#> [1] "found" "found" "found"
#> attr(,"uri")
#> [1] "http://www.gbif.org/species/2704179"
#> [2] "http://www.gbif.org/species/2435099"
#> [3] "http://www.gbif.org/species/3171445"

These as.*() functions do a quick check of the web resource to make sure it's a real ID. However, you can turn this check off, making this coercion much faster:

system.time( replicate(3, as.gbifid(c("2704179","2435099","3171445"), check=TRUE)) )
#>    user  system elapsed 
#>   0.202   0.007   2.191
system.time( replicate(3, as.gbifid(c("2704179","2435099","3171445"), check=FALSE)) )
#>    user  system elapsed 
#>   0.001   0.000   0.000

What taxa are downstream of my taxon of interest?

If someone is not a taxonomic specialist on a particular taxon he likely does not know what children taxa are within a family, or within a genus. This task becomes especially unwieldy when there are a large number of taxa downstream. You can of course go to a website like Wikispecies or Encyclopedia of Life to get downstream names. However, taxize provides an easy way to programatically search for downstream taxa, both for the Catalogue of Life (CoL) and the Integrated Taxonomic Information System. Here is a short example using the CoL in which we want to find all the species within the genus Apis (honey bees).

downstream("Apis", downto = "Species", db = "col")
#> 
#> Retrieving data for taxon 'Apis'
#> $Apis
#>   childtaxa_id     childtaxa_name childtaxa_rank
#> 1      6971712 Apis andreniformis        Species
#> 2      6971713        Apis cerana        Species
#> 3      6971714       Apis dorsata        Species
#> 4      6971715        Apis florea        Species
#> 5      6971716 Apis koschevnikovi        Species
#> 6      6845885     Apis mellifera        Species
#> 7      6971717   Apis nigrocincta        Species
#> 
#> attr(,"class")
#> [1] "downstream"
#> attr(,"db")
#> [1] "col"

We can also request data from ITIS

downstream("Apis", downto = "Species", db = "itis")
#> 
#> Retrieving data for taxon 'Apis'
#> $Apis
#>      tsn parentname parenttsn          taxonname rankid rankname
#> 1 154396       Apis    154395     Apis mellifera    220  Species
#> 2 763550       Apis    154395 Apis andreniformis    220  Species
#> 3 763551       Apis    154395        Apis cerana    220  Species
#> 4 763552       Apis    154395       Apis dorsata    220  Species
#> 5 763553       Apis    154395        Apis florea    220  Species
#> 6 763554       Apis    154395 Apis koschevnikovi    220  Species
#> 7 763555       Apis    154395   Apis nigrocincta    220  Species
#> 
#> attr(,"class")
#> [1] "downstream"
#> attr(,"db")
#> [1] "itis"

Direct children

You may sometimes only want the direct children. We got you covered on that front, with methods for ITIS, NCBI, and Catalogue of Life. For example, let's get direct children (species in this case) of the bee genus Apis using COL data:

children(get_colid("Apis"))
#> 
#> Retrieving data for taxon 'Apis'
#> $`20126217`
#>   childtaxa_id     childtaxa_name childtaxa_rank
#> 1      6971712 Apis andreniformis        Species
#> 2      6971713        Apis cerana        Species
#> 3      6971714       Apis dorsata        Species
#> 4      6971715        Apis florea        Species
#> 5      6971716 Apis koschevnikovi        Species
#> 6      6845885     Apis mellifera        Species
#> 7      6971717   Apis nigrocincta        Species
#> 
#> attr(,"class")
#> [1] "children"
#> attr(,"db")
#> [1] "col"

The direct children (genera in this case) of Pinaceae using NCBI data:

children("Pinaceae", db = "ncbi")
#> $Pinaceae
#>    childtaxa_id childtaxa_name childtaxa_rank
#> 1        123600     Nothotsuga          genus
#> 2         64685        Cathaya          genus
#> 3          3358          Tsuga          genus
#> 4          3356    Pseudotsuga          genus
#> 5          3354    Pseudolarix          genus
#> 6          3337          Pinus          genus
#> 7          3328          Picea          genus
#> 8          3325          Larix          genus
#> 9          3323     Keteleeria          genus
#> 10         3321         Cedrus          genus
#> 11         3319          Abies          genus
#> 
#> attr(,"class")
#> [1] "children"
#> attr(,"db")
#> [1] "ncbi"

Get NCBI ID from GenBank Ids

With accession numbers

genbank2uid(id = 'AJ748748')
#> [1] "282199"
#> attr(,"class")
#> [1] "uid"
#> attr(,"match")
#> [1] "found"
#> attr(,"uri")
#> [1] "http://www.ncbi.nlm.nih.gov/taxonomy/282199"

With gi numbers

genbank2uid(id = 62689767)
#> [1] "282199"
#> attr(,"class")
#> [1] "uid"
#> attr(,"match")
#> [1] "found"
#> attr(,"uri")
#> [1] "http://www.ncbi.nlm.nih.gov/taxonomy/282199"

Matching species tables with different taxonomic resolution

Biologist often need to match different sets of data tied to species. For example, trait-based approaches are a promising tool in ecology. One problem is that abundance data must be matched with trait databases. These two data tables may contain species information on different taxonomic levels and possibly data must be aggregated to a joint taxonomic level, so that the data can be merged. taxize can help in this data-cleaning step, providing a reproducible workflow:

We can use the mentioned classification-function to retrieve the taxonomic hierarchy and then search the hierarchies up- and downwards for matches. Here is an example to match a species with names on three different taxonomic levels.

A <- "gammarus roeseli"

B1 <- "gammarus roeseli"
B2 <- "gammarus"
B3 <- "gammaridae"

A_clas <- classification(A, db = 'ncbi')
B1_clas <- classification(B1, db = 'ncbi')
B2_clas <- classification(B2, db = 'ncbi')
B3_clas <- classification(B3, db = 'ncbi')

B1[match(A, B1)]
#> [1] "gammarus roeseli"
A_clas[[1]]$rank[tolower(A_clas[[1]]$name) %in% B2]
#> [1] "genus"
A_clas[[1]]$rank[tolower(A_clas[[1]]$name) %in% B3]
#> [1] "family"

If we find a direct match (here Gammarus roeseli), we are lucky. But we can also match Gammaridae with Gammarus roeseli, but on a lower taxonomic level. A more comprehensive and realistic example (matching a trait table with an abundance table) is given in the vignette on matching.