I was not trying to give you a lesson, so don't take offense to it. But even if I did give a lesson, what's wrong with it? Is there anything wrong with learning new information? I am just discussing things here. If you want to learn from it or not is up to you. You should see some of the heated debates going on in some scientific circles, but nobody will take offense to corrections, especially ones that can be backed up with established information.
Before I go into what you said, let me just say that Wikipedia, as well-meant of an idea as it is, is not a very good or reliable source. Anyone can go in there and change the information provided, even people that provide wrong or misleading information (although they mean it well). For example Wikipedia's entry "Branchiopoda is a group of primarily fresh water crustaceans,
mostly resembling shrimp" is just plain nonsense as the discussion below will show. That's just reality. Academic institutions are a better, authoritative source for such information. After all scientists provide that information and not "Joe Shmoe" who happens to have found Wikipedia and decides to make an entry.
Although your information is correct that they are all Branchiopoda, that does not mean that they are "closely" related. Branchiopoda is the "class" level. Then, further below, you have the different "orders" within a class. Then you have the different "families" within an order. Within a family you have the different "genera" (singular: "genus"). Then, finally, within the genera you have various species. Additionally, you can have "subclasses", "superorders", "suborders", "superfamilies", "subfamilies" etc. to further classify different animals.
So, let's analyze exactly what you said:
badflash wrote:Monia are the smallest species of water flea and the easiest to keep. Daphnia are a large variety but have some real limits when trying to raise them. They are in the shrimp family closely related to fairy shrimp, artemia, and Triops.
You are saying that they are in the "shrimp" family. There is no such thing as a "shrimp" family. They are Branchiopoda, which is a "class." The "shrimp" we are talking about on this website and keeping in our tanks are in the class "Malacostraca". So, they are in a totally different class! To make clear to you how "closely" related let's say a Red Cherry Shrimp (class malacostraca) to a water flea (class branchiopoda) is I will show you classes of more familiar animals. Maybe then it will become clear that these animals cannot be considered "closely related" at all:
http://www.sidwell.edu/us/science/vlb5/ ... ertebrata/
In the above link you see the Phylum Chordata and within it more specifically the subphylum Vertebrata. There you finally see the different "classes." So, as you can see, what you said would be the equivalent of saying that a frog (class Amphibia) would be "closely" related to an Elephant (class Mammalia). I hope this clarifies the first point.
Now to your second point, your claim that daphnia, fairy shrimp and triops are "closely" related. They are all in the same class, Branchiopoda, but in totally different orders! To use the example of more familiar animals again, look at the following link that shows you the different orders within the class mammalia:
http://animaldiversity.ummz.umich.edu/s ... l#Mammalia
So, saying that Daphnia, fairy shrimp and triops are closely related is like saying that a horse (order Perissodactyla), a baboon (order Primates) and a sea cow or manatee (order Sirenia) are closely related.
To show you that even within the *same* order animals would not necessarily be considered "closely related" I'll give you another example:
http://animaldiversity.ummz.umich.edu/s ... #Carnivora
The above link leads you to the order "Carnivora". Within that order is the family Felidae and the family Odobenidae. So, to say that a Lion and a Walrus are "closely related" would, again, seem nonsensical.
So, although I used a hyperbole to make this point clear earlier (by using bees and ants as an example) you see that the hyperbole was not far off. Considering animals in different orders or even different classes "closely related" is anything else but correct. It's just that most people are not familiar with these tiny animals and more easily accept the claim that they are closely related than a claim that a frog and and elephant are closely related, which would seem outragously wrong to most.
I hope this clarifies things once and for all. I tried avoiding going into such detail as this information can be looked up by anyone, but apparently an explanation this detailed was required to set things straight. And that's what it's all about, presenting the correct information backed up by as much scientific evidence as possible.