Volker Von Wirth & Haplopelma schmidti "Gold Morph" x S. hainana

[phormingochilus]

So what do you think of Ornithoctonus aureotibialis and Ornithoctonus sp. "Surat Thani" - they do live sympatric and are obviously closely related but definitely different from each other?

Regards
Søren

Another interesting exemple of unusual(?) speciation in the Cichlid family :
http://download.naturkundemuseum-berlin.de/thomas.rintelen/schliewen%20&%20klee%202004.pdf

Others species of hybrid origin are known in this family, 2 or 3 are proven but they may be more ones. Also some Drosera species (sundews, insectivorous plants) are of hybrid origin. Speciation by hybridization is maybe more common than we think. Maybe not in theraphosids. Ways of speciations are numerous but I can't see any pair of species as exemple of sympatric speciation in theraphosids, or 3 sympatric species with one being a potential hybrid. Cichlids seems to have weak reproductive barriers and reproductive cycles are shorter than Theraphosids', so they evolve at fast rate.

Cheers, Michael

 

[Steve Nunn]

So what do you think of Ornithoctonus aureotibialis and Ornithoctonus sp. "Surat Thani" - they do live sympatric and are obviously closely related but definitely different from each other?

Hi Søren,
I would guess closely related but recently reintroduced to each other after the loss of a previous barrier of some sort. If the forms remain, they may be different species according to the BSC, if they are in the process of change, anyones guess

It is hard to guess what is coming, going, or staying, that's about as simple as I could make it I think But, because we see them now right here and they are real entities (and not some proposed higher level) I would happily follow the BSC to define them as distinct species as we see them in 2006 But, that's just me.

Steve

 

[Crotalus]

So what do you think of Ornithoctonus aureotibialis and Ornithoctonus sp. "Surat Thani" - they do live sympatric and are obviously closely related but definitely different from each other?

Regards
Søren

Why are they "definitely different"?
How many of them have been found in that area?

/Lelle

 

[phormingochilus]

The eternal sceptic ;-) Let's just conclude that O. aureotibialis is very very VERY common in that area, but with a tendency to congregate on the western side whereas O. sp. "Surat Thani" is equally common but with a tendency to congregate on the eastern side, however both species can be found in both east and west. Thus they are sympatric. That they are in fact two species are implied by many dfferent parameters and characters, none of which would be fair to share here before any official description. I tend to agree with Steve, but I don't neccesarily need any previous barriers to make the puzzle fit ;-) For the barriers could easily be present still - due to one or more mutations in the genes that were far-reaching enough to initiate speciation.

Regards
Søren

Why are they "definitely different"?
How many of them have been found in that area?

/Lelle

 

[FryLock]

Also if a few organisms within a population show a return to a ancestral breeding behaviour that differs enough from the current norm for there given taxa as to exclude them from the "gene herd" that could in theory lead to a sympatric speciation event.

 

[Michael.NEGRINI]

Hello Søren,

I was not aware of O. aureotibialis and O. sp. Surat Thani occuring sympatrically, it's very interesting, thanks.

Do you think they were at first allospecies, that now have extended their distribution and overlap; or maybe an exemple of sympatric speciation ?

Are they sharing the same preferences of suitable microhabitat ?
I don't know if males are emerging at the same time of the year, or if they have different reproductive season...Reproductive behaviour have to be a bit different, or partner choice is easy for them (pheromones ? or mature males/females playing a different rythm when they meet ?).

Just a guessing game, I think you know these far better than me.

Cheers, Michael

 

[Crotalus]

The eternal sceptic ;-) Let's just conclude that O. aureotibialis is very very VERY common in that area, but with a tendency to congregate on the western side whereas O. sp. "Surat Thani" is equally common but with a tendency to congregate on the eastern side, however both species can be found in both east and west. Thus they are sympatric. That they are in fact two species are implied by many dfferent parameters and characters, none of which would be fair to share here before any official description. I tend to agree with Steve, but I don't neccesarily need any previous barriers to make the puzzle fit ;-) For the barriers could easily be present still - due to one or more mutations in the genes that were far-reaching enough to initiate speciation.

Regards
Søren

I have no opinion wheather its a species or not since I have no information about this species - its just questions.
There might been a barrier there once, islands that are now part of the mainland etc
Well we just have to wait for the paper then!

 

[phormingochilus]

Hi Michael

Both of your speciation models could be the one. I don't really know.

For the microhabitat - this is the same - no surprise here. For the mating season - this is usually determined by the annual fluctuations in climate, so will tend to be the same period of the year in both species. But structure of palpal bulb could be different, or genetic make-up could hinder hybridisation etc.

Regards
Søren

Hello Søren,

I was not aware of O. aureotibialis and O. sp. Surat Thani occuring sympatrically, it's very interesting, thanks.

Do you think they were at first allospecies, that now have extended their distribution and overlap; or maybe an exemple of sympatric speciation ?

Are they sharing the same preferences of suitable microhabitat ?
I don't know if males are emerging at the same time of the year, or if they have different reproductive season...Reproductive behaviour have to be a bit different, or partner choice is easy for them (pheromones ? or mature males/females playing a different rythm when they meet ?).

Just a guessing game, I think you know these far better than me.

Cheers, Michael