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AnastomosisJihad
Hominid



Registered: 01/01/08
Posts: 700
Loc: Ohio
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Re: Taxonomical Significance of Microscopic Characters. [Re: ToxicMan]
#7940633 - 01/27/08 02:47 PM (16 years, 5 days ago) |
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Quote:
ToxicMan said: In mycology traditionally, species have been separated on the basis of compatibility between spores. Spores only have have the full set of chromosomes (much as a sperm or ovum), and germinate to form an asexual mold. If two compatible molds of the same species meet, they form a single organism, typically forming clamp connections so that nuclei can travel from cell to cell and complete the full set. If the molds are incompatible, a zone forms between them where each secretes toxins to repel the other. So if spores from 2 specimens are germinated in petri dishes and they are found to be compatible with each other, they are taken to be the same species.
^^^^^This is clearly a "biological species concept".
Quote:
Strophariaceae said: The biological species concept – that if organisms from two populations can breed and produce fertile offspring, they're the same species – doesn't always work well with fungi because fungi often retain interfertility well after they've gone on different evolutionary "tracks". This idea is based on the idea that, in some genera such as Armillaria, closely related species that nonetheless are separated by continental distances and are thought to have been out of contact with each other for many millions of years, nonetheless remain interfertile. (Even though they may lack interfertility with other relatives even in the same locality.)
So you are saying that certain populations of Honey Mushrooms are different species, even though they can interbreed and produce viable off spring?
If two species can be interfertile, then how do you fit their offspring into a cladogram?
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Edited by AnastomosisJihad (01/27/08 02:51 PM)
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GGreatOne234
Stranger
Registered: 12/23/99
Posts: 8,946
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Re: Taxonomical Significance of Microscopic Characters. [Re: AnastomosisJihad]
#7940661 - 01/27/08 02:50 PM (16 years, 5 days ago) |
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AnastomosisJihad, if the universe was somehow put on pause for 1000 years and i was the only one able to to do anything, and i spent the time reading every single known college text book and scientific journal that was ever published, i still would not have even scratched the surface of what is really happening.
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AnastomosisJihad
Hominid



Registered: 01/01/08
Posts: 700
Loc: Ohio
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Re: Taxonomical Significance of Microscopic Characters. [Re: GGreatOne234]
#7940906 - 01/27/08 03:32 PM (16 years, 5 days ago) |
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I'm a little more optimistic.
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AnastomosisJihad
Hominid



Registered: 01/01/08
Posts: 700
Loc: Ohio
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Re: Taxonomical Significance of Microscopic Characters. [Re: Strophariaceae]
#7941036 - 01/27/08 03:54 PM (16 years, 5 days ago) |
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Quote:
Well, the morphological species concept isn't a "real" species concept, but simply a working assumption on the part of mycologists who don't have the knowledge or resources to determine what actual species-level differences are.
If you think about it, the morphological species concept is inescapable. Even if there are essential species, and even if a perfect description of every species fell from the sky, we would still find ourselves relying on morphological characters (macro, micro, and molecular) to determine the species of any given specimen. The morphological species concept is the epistemic counterpart to any ontology of species.
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GGreatOne234
Stranger
Registered: 12/23/99
Posts: 8,946
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Re: Taxonomical Significance of Microscopic Characters. [Re: AnastomosisJihad]
#7941079 - 01/27/08 04:04 PM (16 years, 5 days ago) |
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ok, why is there lightning? not just from a science book about why they think it happens, but why does lightning really happen?
why is a tomatoe red?
why are most reishi mushrooms so brilliantly colored? what is the real reason.
why did i decide to wear brown sneakers today?
here is a good one for the optimistic, why are there psychoactive compounds in some mushrooms? why do they stain blue? do you really think anyone could ever find the real answer.
why did einstein just discover how to blow up a sub-microscopic atomic bomb, instead of how to explode the whole universe?
kind of off topic i guess, but those are some honest questions that i urge you to answer for me. i do not believe that it is possible for a human to answer them. but, maybe you are the exception to the possibilities to what humans can understand. yes, i am quite pessimistic about it, because i personally believe that humans are the dumbest organisms on the planet.
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AnastomosisJihad
Hominid



Registered: 01/01/08
Posts: 700
Loc: Ohio
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Re: Taxonomical Significance of Microscopic Characters. [Re: GGreatOne234]
#7941778 - 01/27/08 06:18 PM (16 years, 5 days ago) |
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Why are tomatoes red?
Quote:
Tomatoes are "RED" because it contains a carrotenoid known as "Lycopene". Lycopene is a terpene assembled from 8 isoprene units. The color of lycopene is due to its many conjugated carbon double bonds. Each double bond reduces the energy required for electrons to transition to higher energy states, allowing the molecule to absorb visible light of progressively longer wavelengths. Lycopene absorbs most of the visible spectrum, so it appears red.
http://answers.yahoo.com/question/index?qid=20061001083616AAAbgi9
Your other questions are too easy. Try google.
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GGreatOne234
Stranger
Registered: 12/23/99
Posts: 8,946
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Re: Taxonomical Significance of Microscopic Characters. [Re: AnastomosisJihad]
#7941905 - 01/27/08 06:36 PM (16 years, 5 days ago) |
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alright smartass i figured you would rebutle with something like that.
ok, why is "lycopene" found in tomatoes? why not a different "carrotenoid" or whatever that makes them Blue like a blueberry? or why do tomatoes have carrotenoid at all? why was it put there? if carrotenoid is found on other planets, is it the same exact thing?
why are tomatoe stalks and leaves the shape they are? over millions of years, why did the leaves turn out that shape? -no need to google search morphology of plants. why would the leaves not be similar in shape to Cannabis or Oregano? do tomatoe-like plants grow on the closest Earth-like planet to us also? if so, what do they look like?
and, what time is it right now on Mars? is it January 27th, 2008 on Mars right now? how about one of those planets in the andromeda galaxy, let's say in the dead center nucleus or core of one of those planets, is it January 27th 2008 there too?
does Ganoderma lucidum grow from hardwoods on planets 80,000,000 light years away from our solar system? or is it slightly different, or non existent any where else but Earth?
my appologize to stropharia for going off topic here
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Strophariaceae
mycologist


Registered: 02/02/04
Posts: 109
Loc: Marvelous Marin County, C...
Last seen: 7 years, 3 months
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Re: Taxonomical Significance of Microscopic Characters. [Re: AnastomosisJihad]
#7949865 - 01/29/08 10:30 AM (16 years, 3 days ago) |
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Quote:
AnastomosisJihad said:
Quote:
Strophariaceae said: The biological species concept – that if organisms from two populations can breed and produce fertile offspring, they're the same species – doesn't always work well with fungi because fungi often retain interfertility well after they've gone on different evolutionary "tracks". This idea is based on the idea that, in some genera such as Armillaria, closely related species that nonetheless are separated by continental distances and are thought to have been out of contact with each other for many millions of years, nonetheless remain interfertile. (Even though they may lack interfertility with other relatives even in the same locality.)
So you are saying that certain populations of Honey Mushrooms are different species, even though they can interbreed and produce viable off spring?
If two species can be interfertile, then how do you fit their offspring into a cladogram?
There's a big difference between saying two species can be interfertile and two species are interfertile. If the two closely-related species are separated by continental differences, its safe to say that, barring reintroduction of one species to the same area as the other, the two populations are separate and evolutionarily distinct. (Oh, and the old idea that atmospheric spore dispersal spread spores so widely that species and population migration is common is an idea that's been pretty thoroughly debunked. Only a few spores ever make it even a few miles from the sporocarp they came from. Of course, these days, there are all kinds of human-mediated species introductions all over the place, but that's something that's extremely recent on an evolutionary time scale.)
How would that fit on a cladogram? Why would one even try to fit a known hybrid on a cladogram?
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AnastomosisJihad
Hominid



Registered: 01/01/08
Posts: 700
Loc: Ohio
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Re: Taxonomical Significance of Microscopic Characters. [Re: Strophariaceae]
#7951607 - 01/29/08 05:42 PM (16 years, 3 days ago) |
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Quote:
Of course, these days, there are all kinds of human-mediated species introductions all over the place, but that's something that's extremely recent on an evolutionary time scale.)
Human mediated species introductions, though recent in timescales required for Darwinian evolution, predate the art of taxonomy by tens of thousands of years. It seems likely to me that some of the 'natural species' described in early taxonomies are actually naturalized hybrids, resulting from crosses of indigenous populations with seeds and spores carried by migrating populations of humans. Homo sapiens were ubiquitous before taxonomy began in earnest.
Quote:
The old idea that atmospheric spore dispersal spread spores so widely that species and population migration is common is an idea that's been pretty thoroughly debunked. Only a few spores ever make it even a few miles from the sporocarp they came from.
I have been in patches of Honey Mushrooms that stretched for miles and produced hundreds of thousands of fruit bodies. Populations of that size produce astronomical numbers of spores. Most of them land within a few inches of the fruit body, but some get carried by the wind. Hurricanes, tornadoes, and simple thermal columns can lift surface air to altitudes of tens of thousands of feet. I think "debunked" might to too strong a claim. Even if no direct evidence of long range spore dispersal has been found, the wind is certainly capable of carrying dust a long way. Particulate pollution from Russian industry frequently makes its way into North America, so there is little reason to suspect a few mushroom spores might not also follow the same vector.
Animal vectors are also something to consider. A flock of migrating birds that stops to rest in a massive patch of mushrooms will certainly carry some spores with them when the move on.
Large populations of mushrooms are also frequently accompanied by large populations of fungus gnats, so there is another vector for spore dispersal.
Quote:
How would that fit on a cladogram? Why would one even try to fit a known hybrid on a cladogram?
"By 1751 Linnaeus considered most species to be of hybrid origin (Olby 1985)" This is from Loren H. Rieseberge's and Mark E. Welch's Gene Transfer Through introgressive Hybridization: History, Evolutionary significance, and Phylogenetic Consequences.
Chapter 18 in Syvanen's and Kado's anthology Horizontal Gene Transfer
The same article notes the often cited statistic that 80% of all plant species arose through hybridization. Cladistic analysis cannot account for hybrids due to restraints of the model, and, if a model of evolution cannot account for 80 percent of the organisms in a major phylum, then it is not a very useful model.
If you find this kind of stuff interesting (Like I do ) then you might want to check out that anthology. I'm sure it is available in you university library.
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NWDude
Stranger
Registered: 09/12/07
Posts: 42
Last seen: 15 years, 2 months
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Re: Taxonomical Significance of Microscopic Characters. [Re: ToxicMan]
#7954222 - 01/30/08 01:06 AM (16 years, 3 days ago) |
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Hey, guys I dont know any thing about this stuf but is it posible for basidia and cystidia to form on a spore?
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Strophariaceae
mycologist



Registered: 02/02/04
Posts: 109
Loc: Marvelous Marin County, C...
Last seen: 7 years, 3 months
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Re: Taxonomical Significance of Microscopic Characters. [Re: NWDude]
#7954234 - 01/30/08 01:10 AM (16 years, 3 days ago) |
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Quote:
NWDude said: Hey, guys I dont know any thing about this stuf but is it posible for basidia and cystidia to form on a spore?
No.
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Alan Rockefeller
Mycologist


Registered: 03/10/07
Posts: 48,276
Last seen: 29 minutes, 47 seconds
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Re: Taxonomical Significance of Microscopic Characters. [Re: NWDude]
#7955132 - 01/30/08 11:15 AM (16 years, 2 days ago) |
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> Hey, guys I dont know any thing about this stuf but is it posible for basidia and cystidia to form on a spore?
Excellent question, I have often wondered that myself.
The answer is that it is not possible.
It is possible for basidia to form a spore, and it can do that while it is next to a cystidia. I hope that is close enough for you.
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AnastomosisJihad
Hominid



Registered: 01/01/08
Posts: 700
Loc: Ohio
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Re: Taxonomical Significance of Microscopic Characters. [Re: Alan Rockefeller]
#7955240 - 01/30/08 11:54 AM (16 years, 2 days ago) |
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A spore starts as a bulge in a special gill cell called a basidium. Usually two or four bulges will begin simultaneously, giving a crown or fingered look to the basidium.
 Wikipedia basidium
As the bulges form, a vacuole begins expanding at the other end of the basidium. As it expands the vacuole pushes all the guts of the basidium into the forming spores. Once the spores are full, the cell walls close and the spores launch themselves off the gill edge in a process that Strophariaceae describes here.
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