What is a head?

[cmungall]

In ZFA, a head is analagous to a mammalian head+neck.

This causes problems when we bring in spatial disjointness (see issue #378 )

The def of head is pretty vague:

def: "The head is the anterior-most division of the body [GO]." [GO:0060322, Wikipedia:Head]

What's a division?

We introduced a grouping class to accommodate this:

• UBERON:0007811 ! craniocervical region [DEF: "The anteriormost subdivision of the body that includes the head, jaws, pharyngeal region and the neck (if present). In vertebrates this is the subdivision that includes the cervical vertebrae."]
  • UBERON:0000033 ! head [DEF: "The head is the anterior-most division of the body [GO]."]
  • UBERON:0000974 ! neck [DEF: "Subdivision of body proper, which consists of a maximal set of diverse subclasses of organ and organ part spatially associated with the cervical vertebral coumn, it is partially surrounded by skin of neck. Examples: There is only one neck[FMA]."]

Should ZFA head be mapped to this parent class?

For now, only consider vertebrates - let's not get into the insect head problem...

Note: objections have been raised in the past about the term "craniocervical region". But I think we need some kind of logical structure like this regardless of what we call it.

One option is to call the parent "head" and the child "tetrapod head", but this is ugly, and would make the ontology confusing for mammalian users who expect the head to be... the head.