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Unread 12/27/2001, 11:22 PM   #11
saltshop
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Just to wrap this up since Adam is inclined to quit already... Figured I would hit on some of the stuff which Dr. Ron did not cover.

Originally posted by Adam


Have you read the literature for yourself? Alot of others have, and have a different interpretation.

Crazy enough but I actually have read a fair portion of what is on Dr. Ron's site. While some of the references he listed were a little "obscure" when it came to the subject matter at hand some were very good reads and well worth the time. As for the "others" that you speak of if you were to look into it and not take it on faith you will find that the main one in particular has a very annoying habit of stretching and bending the truth whenever he is challenged. This was written in a past debate on this subject:

"including Veron himself, since he is quite skeptical of your theory"

Now lets see what Veron himself "actually thinks" about temperature and its relatedness to biodiversity shall we? These are all from Corals in Space and Time since it is handy and I just re-read the thing for the third time.

"Latitudinal attenuation occurs in the same or similar 'drop-out' sequence in the northrn and southern hemisheres. Latitudinal attenuation is highly correlated with sea surface temperature." pg. 47

"It has long been known that latitudinal range is primarily limited by temperature or correlates of temperature pg. 75

"These data demonstrate that, within Japan, coral species richness can be predicted almost solely from sea surface temperature"...."In the case of central Indo-Pacific latitudinal gradients, this correlation shows that it is temperature and the correlates of temperature, not dispersion capability that is limiting pg. 93

If he is skeptical he sure has a funny way of showing it in his writings. My guess is that the thoughts were passed on to him in a conversation saying something like "Dr. Shimek thinks that ONLY temperature is responsible for diversity banding" or something to that effect that would take the subject out of context to skew the argument.


Your right, sorry for my semantic error. Growth in many species(until you reach an upper thermal limit) is greater at higher temps.

No not "many", but almost all with exception of a few highly tolerant species and some odd-ball deep water species.


As far as Veron's books are concerned... I won't speak about the exact statements made, but in Corals of the World, alot of factors affecting maximum diversity are discussed. Temperature is one, but sunlight and geographical features are also important.

Yes, there are dozens if not more factors that affect diversity and all are important. But a lot of those factors are more regional and local in scale compared to general biodiversity that relates mainly with temperature and surface currents. If you or any other skeptic were to ask Dr. Ron I think you would find he agrees with most of these other factors when it comes to local species diversity be it niche habitats or physical stressors, or whatever you so choose to ask. You cannot however, replace general over-riding factors with localized factors and say that this shows temperature is less important or a non-factor as the two come from different chapters and are best discussed seperately or in conjuction with one another.

If temp is the major factor, why is diversity so much less in the tropical atlantic? It is just as warm as the indo pacific, right?

If you have to ask that one I suggest picking up some texts on biogeography. This is like Biogeography 101 first chapter stuff be it the genetic isolation, human factors, geographic factors, the closing of the Isthmus of Panama..yadda yadda, yadda....

It is because the near surface geological structures aren't there for the corals to grow on.

Actually it has more to do with genetic isolation and the homogeneous structure of the area that has effected speciation.

Also, why is diversity not the highest in the Red Sea? It gets warmer there than the central Indo Pacific.

Again, 101 stuff... The Red Sea has become land locked several times in recent geological history causing mass extinctions from salinity crises more than anything. There is also the matter of the vast nothingness of the Indian Ocean.


The argument that corals are somehow slowly dying at temps below 80-84 just doesn't hold water.

This was the main sticking point originally in the past debates and it is true 100-200 species can live in environments at temperauters below this. Those species that are able to tolerate the lower temps have shown that they indeed can survive grow and even reproduce at those temps. However, there are 300-400 species that cannot survive temperatures below this, or least have not yet to date.


Even if you do believe that the average (over several years) temperature of all the reefs is 82, how long has it been that way in evolutionary terms??

This is not something that you can either believe or dis-believe it is just so. If you choose to ignore facts just to fit whatever your thinking is then so be it.

This interestingly corresponds to the increase in bleaching events in the last few years.

Actually, there is some thoughts that there have been periods of bleaching events ever since the Isthmus of Panama closed seperating the worlds oceans we just weren't paying attention at the time. This has been neither proven or dis-proven so take it FWIW.

The temp in Fiji is too cold for the survival of what???

Approximately 300-400+ species of stoney coral currently cannot or do not survive in the waters of Fiji last I checked.

Get out your Veron books, and see what the diversity is in southern Japan, which gets much cooler than the 77 degrees you state as the coldest reef known.

Japan has the good fortune of having the strongest latitudinal current in the Kuroshio Current which brings warm water (and planulae) north from the center of the Indo-Pacific. Those areas with average temperatures below 77F are not reefal communities but mainly algal reefs with a sparse population of corals.

It certainly is less than the central indo-pacific, but it is much greater than the tropical east atlantic!

Yes, it is greater than the Atlantic because it does not suffer from genetic isolation.

I guess that about sums it up for now.


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