Phase vs Morph

[MasonC2K]

Could someone please explain what, if any, the difference is between these?

When I first saw the word phase, I assumed it was like a temporary appearance based on something like age or the time of year or something. But reading more, it appears to be the full time appearance.

So is phase just another way people say morph?

Thanks.

[mainbutter]

Neither are scientific terms, which makes things especially tricky. Both tend to imply that offspring will look like the parents. Phase tends to imply line-bred or locality specific visual appearance, though (particularly with geckos) "morph" is used in the same way on occasion.

Sometimes "phase" can be used to describe a subset of individuals of a particular "morph" that have a distinct look, such as with "white phase albino reticulated pythons". In that instance, the morph is "albino", but it has a wide range of how it may look, typically purple, lavender, or white.

Confused yet?

[MasonC2K]

Confused yet?

Absolutely!

[Russ Lawson]

I have heard the term phase most often applied to two different instances. The first is a temporary change in appearance of an animal, but the time scale can be short as hours at a time or possibly shorter. My example here is with Hog Island boas and how they can go between dark and light phases throughout the day. I've noticed colour changes like this in other boa species as well.

The second use of phase I have heard is more of a locale-type scenario. I can think of Miami phase corn snakes in this manner. They have a distinct contrast between silver/grey and red, which is unique to animals from that locale.

I have never heard the term phase used to describe one specific genetic mutation that results in obvious phenotypical differences. However, from further reading on the subject, it seems that the term phase is somewhat synonymous with phenotype. As we are well aware, the term morph is also synonymous with phenotype, so it wouldn't technically be incorrect to use the two interchangeably. It would just sound strange to us because we are so used to hearing the term morph to describe a mutation that results in change in phenotype.