I'm looking into transfer in second language acquisition, specifically on the syllable structure of other L1s transferring onto English. I'm discussing the impact of transfer as well as the impact of universals, but I confess I don't understand universals too well. I know big factors are markedness and the SSP, but would they come under the influence of universals or the influence of transfer?
It has been claimed that markedness and sonority sequencing are universals, but whether or not they are depends very much on what is meant by "universal". The usual understanding of the notion is that there are certain properties of the language faculty that are hard-wired into "universal grammar", and those are the universals. Markedness is an extremely broad concept, which reduces to listing preferences rather than impossibilities, that is, languages prefer to not have consonant clusters n the onset or coda of a syllable, but they can. A fair number of languages have only one consonant at the beginning of the syllable, and no language has only clusters at the beginning of the syllable, which is said to be a consequence of saying that the preference against onset clusters is "universal". The sonority sequencing premise is a specific kind of markedness claim, that onset clusters of the type [pr,pl,kl] are preferred over [rp,lp,lk], and the mirror-image relation for syllable codas.
There are basically two theoretical camps, in terms of explaining the existence of these patterns. One is that there is some form of hard-wired grammatical principle whereby certain things are dispreferred – this is the Optimality Theory approach. Alternatively, it is argued in the Substance Free approach that the fact patterns are epiphenomenal, and result from language-independent functional considerations, interacting with principles of learning: for example, it is easier to mistake an [lk] onset for [k] than it is to mistake a [kl] onset for [k] (or [l]), and this is not part of the theory of grammar. Both approaches have a means of explaining why complex onsets of English are often simplified by second language learners, they just differ in exactly what the mechanism is. IMO, the hard-universals only account has a somewhat harder time explaining why second language acquisition does not always involve a hard reset to CV syllables: but we know that English speakers do transfer their ability to produce onset and coda clusters to second languages. We also know that speakers of languages with "counter-universal" clustering patterns (allowing NC onsets but otherwise not having consonant clusters) have problems with English [pr,pl...] onsets, again because they have no prior experience with them in their native language, indicating that the grammatical patterns of L1 are transfered to L2.