Paedomorphism/Neoteny (in CC amphib glossary)

[Azhael]

Although commonly used indistinctively, these two terms are essentially different.
Paedomorphism: Phenomenon by which the reproductive organs mature earlier in the development than would be "normal". The result is a larval or juvenile individual with the capacity of reproducing.
Neoteny: Retention of larval or juvenile characteristics in adult individuals. The number of characteristics that are retained is very variable.

 

[Jan]

Neoteny: Retention of larval or juvenile characteristics in adult individuals. The number of characteristics that are retained is very variable.

Should we add 'sexually mature' which would read as:

Neoteny (neotenic): Retention of larval or juvenile characteristics in sexually mature adult individuals. The number of characteristics that are retained is very variable.

And perhaps give some examples of neotenic caudates??

 

[Azhael]

If you consider it makes it easier to understand, it´s perfectly ok with me. For me, "adult" invariably implies sexual maturity, but it may be good to remind people.

 

[blueberlin]

Actually, I understood the word to mean somewhat the opposite: the ability to reproduce in a larval or juvenile state.

-Eva

 

[Jan]

Actually, I understood the word to mean somewhat the opposite: the ability to reproduce in a larval or juvenile state.

-Eva

Larva by definiton means sexually immature and unable to reproduce...I believe.
In neoteny, the rate of growth of somatic parts of the body is slowed whereas development of reproductive organs proceeds normally.

 

[Azhael]

The definitions available on different sources for both terms are extremely confusing :S You can find the same definition for both terms interchangeably, sometimes they are down right used as sinonyms...pfffff....i find it tedious.
The ones i gave above are taken from an explanation given from my Chordates professor (i´m more inclined to believe him than wikipedia....), and i have to admit it was the first time i actually understood them.

 

[Jan]

The definitions available on different sources for both terms are extremely confusing :S You can find the same definition for both terms interchangeably, sometimes they are down right used as sinonyms...pfffff....i find it tedious.
The ones i gave above are taken from an explanation given from my Chordates professor (i´m more inclined to believe him than wikipedia....), and i have to admit it was the first time i actually understood them.

I understand neoteny to be as you described it - I just wanted a reminder/clarification placed in the definiton as to sexual maturity. Are we still agreed that we can use your definition with my clarification/reminder?

 

[Azhael]

Of course, Jan.

 

[blueberlin]

Since I piped in earlier I'll say ok too.

@Jan: Thanks, it makes much more sense to me how you wrote it.

-Eva, measuring stick of the average reader :happy:

 

[Jan]

What would you think of this to summarize?:

Paedomorphism: Phenomenon by which the reproductive organs mature earlier in the development than would be "normal". The result is an immature “non-adult” individual with the capacity of reproducing.

Neoteny (neotenic): Retention of larval or juvenile characteristics in sexually mature adult individuals. In these individuals, the rate of growth of somatic parts of the body is slowed whereas development of reproductive organs proceeds normally. The number of larval/juvenile characteristics that are retained is very variable.

 

[Azhael]

I personally see two problems.

In Paedomorphism , although the term "immature" engloves larval/juvenile/sub-adult etc, i think mentioning them is helpful cause it helps realize just how earlier in the development this phenomenon can occur. What do you think of "...the result is an immature (which can be larval, juvenile or sub-adult) individual..."??
This is just a minor detail, though. Your version is technically correct.

With neoteny i have a bigger problem. I think "the rate of growth of somatic parts of the body is slowed" is confusing, because it implies that there is a lesser degree of growth of the animal, which is untrue. I would substitute "growth" for "development" perhaps. The key in neoteny is that the animal is developing normally, except for certain specific characteristics. The way i see it, if there is a slower growth of somatic parts of the body, then what you have is paedomorphism.

Let me know what you think, please.

 

[Jan]

I personally see two problems.

In Paedomorphism , although the term "immature" engloves larval/juvenile/sub-adult etc, i think mentioning them is helpful cause it helps realize just how earlier in the development this phenomenon can occur. What do you think of "...the result is an immature (which can be larval, juvenile or sub-adult) individual..."??
This is just a minor detail, though. Your version is technically correct.

With neoteny i have a bigger problem. I think "the rate of growth of somatic parts of the body is slowed" is confusing, because it implies that there is a lesser degree of growth of the animal, which is untrue. I would substitute "growth" for "development" perhaps. The key in neoteny is that the animal is developing normally, except for certain specific characteristics. The way i see it, if there is a slower growth of somatic parts of the body, then what you have is paedomorphism.

Let me know what you think, please.

Good thoughts and I would mostly agree:

Paedomorphism: Phenomenon by which the reproductive organs mature earlier in the development than would be "normal". The result is an immature (e.g., larval, juvenile or sub-adult) individual with the capacity of reproducing.

Neoteny (neotenic): Retention of larval or juvenile characteristics in sexually mature adult individuals. In these individuals, the rate of development of somatic parts of the body is slowed whereas development of reproductive organs proceeds normally. The number of larval/juvenile characteristics that are retained is very variable.

However, I do not necessarily agree with your statement: "The way i see it, if there is a slower growth of somatic parts of the body, then what you have is paedomorphism". Gonads, intelligence, 'spirit', etc are not considered 'somatic'. You can have an excelerated rate of development of gonads and have a slow development of somatic body parts. A little confusing????

 

[Azhael]

Mmmm.....maybe the problem can be resolved by saying that only certain aspects of the somatic body are slowed = retention of certain larval/juvenile features?? What do you think?

 

[Jan]

Mmmm.....maybe the problem can be resolved by saying that only certain aspects of the somatic body are slowed = retention of certain larval/juvenile features?? What do you think?

Might you propose how you would reword the definition to include this?

 

[Azhael]

Neoteny (neotenic): Retention of larval or juvenile characteristics in sexually mature adult individuals. In these individuals, the rate of development of certain somatic parts of the body is slowed whereas development of reproductive organs and the rest of the somatic body proceeds normally. The number of larval/juvenile characteristics that are retained is very variable.

 

[Jan]

Groovy:happy: - I think these two definitions are ready to be moved to the 'completed' word section unless someone(s) has any other thoughts.

 

[Jan]

Final definitions:

Neoteny (neotenic): Retention of larval or juvenile characteristics in sexually mature adult individuals. In these individuals, the rate of development of certain somatic parts of the body is slowed whereas development of reproductive organs and the rest of the somatic body proceeds normally. The number of larval/juvenile characteristics that are retained is very variable.

Paedomorphism: Phenomenon by which the reproductive organs mature earlier in the development than would be "normal". The result is an immature (e.g., larval, juvenile or sub-adult) individual with the capacity of reproducing.