Tales from the
TreeBundle of Seedlings, or maybe best called Web of Life:
Traditionally, marine microplankton had been divided similarly to species on land. You had plant-like phytoplankton, such as algae, and animal-like zooplankton that ate the phytoplankton. What Stoecker found was that some of these organisms were somewhere in the middle: They could eat like animals when food was present and photosynthesize like plants in the light. “If you think about it, it can be the best of both worlds,” says marine ecologist Dave A. Caron of the University of Southern California.
Today, there’s growing realization that these in-between beasties — dubbed mixotrophs — are not only widespread but also play vital roles in the ecology of the oceans.Rodrigo Pérez Ortega, “Mixing it up in the web of life” at Knowable Magazine
It turns out that these “mixotrophs” are fairly common and they may play a key role in the carbon cycle of the ocean due to their general flexibility (they can also eat each other). No one knows why,k apart from carnivorous plants, mixotrophy is far more common in the ocean than on land.
But none of this does much for traditional biological classifications like “Animal, Vegetable, Mineral” and a tidy Tree of Life.
Maybe horizontal gene transfer was involved? Plankton could adapt swiftly borrowing genes from nearby organism.
See also: A physicist looks at biology’s problem of “speciation” in humans
and
Horizontal gene transfer: Sorry, Darwin, it’s not your evolution any more
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Why not? They don’t mention any evidence that the chloroplasts are inherited.
My problem with the problem of speciation in humans is the constantly-evolving definition of a species.
When I was young (admittedly some decades ago) we were taught that the (note the singular) definition was that two populations were the same species if individuals could (A) interbreed, and (B) produce viable offspring by so doing. This practical animal husbandry rule of thumb served adequately until various interest groups wanted to multiply the species count in accord with their favoured flavour of darwinism.
But IF it is true that there are 7 different species of finches in the Galapagos islands, even though they all successfully interbreed AND produce viable offspring, THEN there is no reason to suppose that a Kalahari bushman and a Norse viking are the same species.
But such political third rails cannot be touched by those whose malleable worldviews are forged and hammered in the fires of public opinion, and so principled applications of logic are foregone in favour of craven self-negations.
There are a significant number of important biological concepts that are not only deserving of challenge, but also of outright rejection. The post-modern definitions of species certainly fit this bill.
Any concept that doesn’t have intrinsic engineering application – see reference to “animal husbandry“, above – is at best speculation. This is merely another way of saying that the proposition must be testable to be worthy of consideration.
In my past life I did research on microplankton and knew Diane Stoecker. She is scary smart.
I don’t see how. These ciliates, which reach concentrations of several per mL of surface water, obtain their chlorophyll from ingesting algae and sequestering the chloroplasts. These cilliates, along with their non photosynthetic cousins, form an important link in the marine food chain transferring energy from bacterioplankton and small algae through copepods to fish.
Marine plankton have always been a passion of mine. Unfortunately employment opportunities were limited when I was young and, frankly, I didn’t have the necessary ambition. Analytical chemistry was just something I fell in to.
Bob O’H
From the article:
Ed George:
And that is where you became familiar with the Acartia genus. 😛
How is mineral a biological classification? I dont think Animal, Vegetable, Mineral has ever been a “traditional classification system” at least not in the last 300 years. I think its probably been known for ~100 years that Euglena is a mixotroph and its never been a problem for classification because classification is not based on whether or not something is photosynthetic but rather its nested set of relationships. So the Euglenids are most closely related to the kinetoplasts such as Trypanosomes – which is a parasite that causes sleeping sickness
ET
I’m not familiar with the genus Acartia. My research invoked spirotrichs, a class of marine ciliates that is found almost everywhere in the ocean surface waters. One group is even found in the interstitial spaces in the ice in the arctic. They can reproduce by asexual fission but need a meritocracy reproduction every so many generations or they will die. One group can cheat this need by undergoing an internal meitic process followed by “self fertilization”. Amazing little critters.
Lantag
I think it is a reference to Linnaeus’ original classification system.
When you were young you were taught the approximate rule that is used in high school biology (and even then often presented with counter-examples). If you continued to study biology you wll have dicussed this and other species concepts more critically. Evolutionary biologists have never thought of the Biological Species Concept as the One True Species Concept (though it was especially influential from the 1940s or so).
It is mistifying why ID keeps bringing up the often blurred lines between species, as if it somehow disproves evolution. Could it possibly be because of the title of Darwin’s book?
BB states “as if it somehow disproves evolution”
Hmm, disproving and/or falsifying a supposedly scientific theory. Interesting concept. I believe Popper may have mentioned something about that:
Lstemarch @ 4 – that quote doesn’t answer my question, I’m afraid.
Brother Brian- Evolutionism cannot account for any species.