Displaying taxonomic classifications from Wikidata using d3js and SPARQL

Following on from previous posts The Semantic Web made fun: d3sparql and The Biodiversity Heritage Library meets Wikidata via Wikispecies: adding author identifiers to BioStor I've put together an example query that can be used to extract a taxonomic classification from Wikidata. The query is inspired by the http://biohackathon.org/d3sparql/ example, and uses the wikidata property P171 ("parent taxon") which is subproperty of rdfs:subClassOf (the property used in the d3sparql example which queries the Uniprot taxonomy).

The following SPARQL query generates a list of nodes in the tree representing the classification of Hominini (humans, chimps, and their extinct relatives):

PREFIX wdt: <http://www.wikidata.org/prop/direct/>
PREFIX wd: <http://www.wikidata.org/entity/>
SELECT ?root_name ?parent_name ?child_name WHERE
{
 VALUES ?root_name {"Hominini"}
 ?root wdt:P225 ?root_name .
 ?child wdt:P171+ ?root .
 ?child wdt:P171 ?parent .
 ?child wdt:P225 ?child_name .
 ?parent wdt:P225 ?parent_name .
}

Using https://query.wikidata.org/sparql as the endpoint, in http://biohackathon.org/d3sparql/ this generates the following diagram:

There are some obvious issues with this classification, such as genera that lack descendant species (e.g., Cyphanthropus). Indeed, we could imagine developing SPARQL queries to flag up such errors (see A use case for RDF in taxonomy). But the availability and accessibility of Wikidata and its SPARQL interface makes it a great playground to explore the utility of SPARQL for exploring taxonomic data.