Pinctada Maculata (Pipi) Pearls

What a ring, Steve! Well done! I'm glad to hear that there's been some regrowth of the beds.

David, always fascinating biological information! I'm interested in doing some genetic research on P. maculata, but would need to find the time, funds and partners. I've just gotten into genetic population structure research with my woodrat project here in NC. It's proven to be vital information on potential population trends.
 
Steve, I've got a few dark ones in my collection as well.
IMG_0464.jpeg
 
Very nice. Yes, the color range stands clarified. At the time of my initial activity over 15 years ago I was not offered the darker shades, for whatever reason. It was only when Poe Pipi from French Polynesia began showing up on this thread that the parameters were broadened.
 
I'm interested in doing some genetic research on P. maculata, but would need to find the time, funds and partners. I've just gotten into genetic population structure research with my woodrat project here in NC. It's proven to be vital information on potential population trends.
That's very intriguing! I could go on forever and a day about genetic diversity. My earliest work was with salmon, but later involved mussels. With the fin fish, we studied the effects of "jacking", which was one thought to be runting. It turned out the fish were not runts, but sexually over-mature for the age group, where males would spawn a year earlier than otherwise expected. Motile milt collected from these males produced near to one hundred percent full sized, normally cycled adults in the hatchery. A classic case of genetic diversity.

In California mussels (Mytilus californianus), studied the behaviour in the transition zones, where the species biomass gives way to Blue mussels (Mytilus edulis). However, we did still find Mytilus c. in calm water, but in limited populations, likely due to greater predator populations. We also stumbled upon hybrids of blue mussels with brown mussels (Mytlus galloprovincialis), producing offspring of each other.

Also in the invasive zebra mussel, where they do not rely on on structural hold-fasting insomuch as clinging to each other. We discovered a subspecies which grew only minimal byssal threads. Enhancing this undermines the other population, thus minimizing, even eliminating the invasion.

Genetic diversity and resiliency studies in otherwise non or marginally commercial biomasses are woefully under-studied.
 
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That's very intriguing! I could go on forever and a day about genetic diversity. My earliest work was with salmon, but later involved mussels. With the fin fish, we studied the effects of "jacking", which was one thought to be runting. It turned out the fish were not runts, but sexually over-mature for the age group, where males would spawn a year earlier than otherwise expected. Motile milt collected from these males produced near to one hundred percent full sized, normally cycled adults in the hatchery. A classic case of genetic diversity.

In California mussels (Mytilus californianus), studied the behaviour in the transition zones, where the species biomass gives way to Blue mussels (Mytilus edulis). However, we did still find Mytilus c. in calm water, but in limited populations, likely due to greater predator populations. We also stumbled upon hybrids of blue mussels with brown mussels (Mytlus galloprovincialis), producing offspring of each other.

Also in the invasive zebra mussel, where they do not rely on on structural hold-fasting insomuch as clinging to each other. We discovered a subspecies which grew only minimal byssal threads. Enhancing this undermines the other population, thus minimizing, even eliminating the invasion.

Genetic diversity and resiliency studies in otherwise non or marginally commercial biomasses are woefully under-studied.
It's difficult to get the funding for research on non-game mammals as well. I had to get a genetics lab to donate their time and running their equipment in order to do my woodrat research. Hybridization is the most interesting point of research to me because of its conservation implications and how the ESA isn't set up to deal with active speciation in imperiled species. It's no doubt we'll continue to see more hybridization between species as the planet keeps warming.
 
Very nice. Yes, the color range stands clarified. At the time of my initial activity over 15 years ago I was not offered the darker shades, for whatever reason. It was only when Poe Pipi from French Polynesia began showing up on this thread that the parameters were broadened.
I've heard that there are some atolls where beds are producing only one color and some where one side of an atoll produces one color while another side produces another color. To me this is fascinating, biologically speaking. What's causing these color differences? Genetics research might enlighten what's going on there.
 
Would it make any sense to open a Marine Sciences thread? There is certainly enough expertise here to moderate such a discussion.
We could call it: the Scientific Corner. But we do have more than enough threads as is!
 
But we do have more than enough threads as is!
Public comment for admin: Thread creation is epidemic, way too easy and the constant deluge of new threads with casual inquiries is especially irritating. Would that more threads would act as catch-all, such as 'Show Us Your Pearls'! What if admin could restrict new thread creation by re-directing to some such umbrella as 'Ask the Experts'? Or maybe a requirement for threads to receive a minimum number of replies to avoid deletion (perhaps such a parameter already exists?). This post, under such consideration, should be moved to a new thread (which I considered)!
 
Public comment for admin: Thread creation is epidemic, way too easy and the constant deluge of new threads with casual inquiries is especially irritating. Would that more threads would act as catch-all, such as 'Show Us Your Pearls'! What if admin could restrict new thread creation by re-directing to some such umbrella as 'Ask the Experts'? Or maybe a requirement for threads to receive a minimum number of replies to avoid deletion (perhaps such a parameter already exists?). This post, under such consideration, should be moved to a new thread (which I considered)!
Will have to look into this tech issue: can thread creation become limited?
 
In the absence of a scientific section, a scientific discussion may arise or be questioned in other threads nonetheless. For some who don't strictly adhere to the tenets of science, comments may be misconstrued as an affront or ill-informed. Whilst incorrect, mythical or all-or-nothing comments are made, these may often derail the original poster's topic or otherwise be moderated/locked by admins without resolution.

P-G is an educational forum, but one of marketing, fashion, history, limited identification etc., but not objective science or research. Not everything in pearl science can be cited, but collective observation, speculation and replication within that context ought to be acceptable. Especially when controls are disclosed or demonstrated. In debunking inaccuracies, falsehoods or pseudoscience, open discussions are what flesh these things out.

I don't buy pearls. I don't (necessarily) sell pearls. I don't wear pearls. I study pearls in biology, archaeology, paleontology, ecology and origin. Even under all of those disciplines, my contribution here is generally confined to identification from limited imagery.

Most of that goes over heads, but there are those where it doesn't. Objective scientific discussion oft requires an extra layer of moderation, thus a reasonable explanation for it's absence. I'm sure the moderators are already considerably burdened in their ongoing tasks.
 
I've heard that there are some atolls where beds are producing only one color and some where one side of an atoll produces one color while another side produces another color. To me this is fascinating, biologically speaking. What's causing these color differences? Genetics research might enlighten what's going on there.
A few years ago I asked a top genetics biologist why shells and therefore pearls had colour in their nacre in some species, given that there was no male/female sex attraction thing going on; that it is mostly dark at the depths at which shells live: and no eyes to see the colours. But there they are.
He couldn't explain it.
Are we just lucky?
 
As to limiting the never ending flood of ' I bought this off ebay for $1 and I think they are natural pearls' and 'I inherited these from...'
Perhaps limit the starting of a new thread to someone with ten posts under their belt or somesuch - like posting photos is limited? Or we just agree to ignore them?
 
As to limiting the never ending flood of ' I bought this off ebay for $1 and I think they are natural pearls' and 'I inherited these from...'
Perhaps limit the starting of a new thread to someone with ten posts under their belt or somesuch - like posting photos is limited? Or we just agree to ignore them?
I enjoy replying to posts of folks who have inherited pearls, and I feel we are doing them a real service in helping them to determine what they are, so they can decide what to do with them.

Also, at times we have been able to help folks avoid being scammed on eBay or on other sites, and sometimes to validate a good purchase. The "What Kind of Pearls Do I Have?" forum was created to help in such situations, and it seems to me it's popular because it's useful.

Photos are essential if we are to help identify pearls. If we only allow people with a certain number of posts to start a thread, we will lose out on helping these folks, as well as all the people who read their posts and benefit from the information, but don't post themselves.

Certainly feel free to ignore such posts if you don't like replying; I don't mind at all.
 
But I didn't say such posts have to be ignored, just confined to a single thread. It was Douglas who initially punted such an idea. Most of the people who post new threads don't bother to read any previous posts or sticky information. I'm glad you enjoy responding. It's a thankless task. often literally.
 
That's so fascinating about the mystery of nacre color, especially as the evolution of shell exterior color/pattern is so intuitively understood.

In my post I neglected the forum-level 'What Kind of Pearls do I Have'—essentially my 'Ask the Experts' suggestion—and would have edited or deleted that but for Douglas's reply quote.

Still seems like Science (with capital 'S') would easily justify a similar focus, potentially attracting a complimentary viewership and resource for members and public. But clearly it is also relevant within thread context.
 
But I didn't say such posts have to be ignored, just confined to a single thread. It was Douglas who initially punted such an idea. Most of the people who post new threads don't bother to read any previous posts or sticky information. I'm glad you enjoy responding. It's a thankless task. often literally.
But since we have an entire forum for this (i.e. What Kind Of Pearls...), why confine them to a single thread?

Some days we have several people asking such a question; if their posts are all on one thread, I could see confusion arising as to which poster we are replying to.
 
A few years ago I asked a top genetics biologist why shells and therefore pearls had colour in their nacre in some species, given that there was no male/female sex attraction thing going on; that it is mostly dark at the depths at which shells live: and no eyes to see the colours. But there they are.
He couldn't explain it.
Are we just lucky?
Andrea is a dedicated scientist, so I'm sure she's okay with us going off track in her thread.

I remember that thread, which seemed odd for a geneticist. For me it's a common sense question. Shells are a biotic structure built to manage strength and permeability in an extreme environment.

However, you've mentioned eyes. Over the years, we've learned brainless mollusks actually possess complex nervous systems. Mantles are a highly tactile surface. We only need to look at cephalapods to gather this. Mantles evolved into a head and tentacle structure. We know their legs to be highly sensitive, agile and manipulative. They have developed nine brains. One for each tentacle and one as a central processing unit. That makes them more evolved than even humans in ways. Mollusks possess chromatophores. I'd suggest these are used to locate existing micro-crystalline structures to determine where to precipitate the next crystal. We know scallops developed eyes superior to the perisostracial mantle. While they're not elaborate, they can process a binary image of their surroundings.

We also know aragonite, is an elegant form of calcium carbonate. It's crystal habits are commonly dendritic or pseudo-hexagonal, but can also be acicular, tabular, prismatic or coral-like. Mollusks have that all figured out and each play an important role in their survival.
 
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