Signed languages in co-existence with Germanic languages: A typological perspective

Human natural languages come in two forms: spoken languages and signed languages, which are the visual-
gestural languages used mainly by Deaf communities. Modern signed language linguistics only began around 1960.
Studies have shown that signed languages share similarities with spoken languages at all levels of linguistic
description, but that modality—whether vocal-auditory or visual-gestural—plays a role in some of the differences
between spoken and signed languages. For example, signed languages show a more simultaneous organization
than spoken languages, and iconicity and the use of space play a more important role. The study of signed
languages is therefore an important addition to our knowledge of human language in general. Based on the
research already carried out, it seems that different signed languages are structurally more similar to each other
than different spoken languages. The striking similarities between signed languages have been attributed to several
factors, including the affordances of the visual-gestural modality. However, more recent research has also shown
differences between signed languages. Some of these may be due to independent diachronic changes in individual
signed languages, others to influences from spoken languages. Indeed, for most signed languages there is an
intensive contact with at least one, and sometimes several, spoken languages, which undoubtedly influence the
signed languages, especially at the lexical level. However, the influence, whether lexical or grammatical, has been
explored to a limited extent. It is particularly interesting to examine the extent to which unrelated signed languages
are similar and different, and whether contact with the surrounding spoken languages plays a role in this.
Danish Sign Language and Flemish Sign Language are two signed languages that are not related. By contrast,
Danish and Dutch both belong to the Germanic language family, Danish as a North Germanic language, Dutch as a
West Germanic language. Some of the features shared by the two signed languages can be explained as modality
dependent: they both use spatial morphology to express agreement and complex verbs of motion and location, and
both use nonmanual features, that is, facial expression, gaze direction, and head movement, to express, for
instance, topicalization and clause boundaries. Other shared features may not be explained as modality dependent
in any straightforward way; this is the case with their preference for sentence-final repetition of pronouns and
verbs. Moreover, the two signed languages share features that distinguish them from most Germanic languages:
they lack a clear subject category and prototypical passive constructions, and they do not have V2-organization
with the finite verb in the second position of declarative clauses. Much more research, especially research based on
large annotated corpora, is needed to clarify the reasons why unrelated signed languages share many grammatical
features, and the influences from spoken languages on signed languages.