"Wouldn't it be
wonderful if the response to the next "anecdote"
being passed around the campfire was, 'HOW DO YOU KNOW
THAT'S TRUE?' "
paraphrase of a statement by Eric Borneman.
At a recent conference, Eric Borneman and
Dr. Rob Toonen both spoke on topics that had as a major theme,
the need for hobbyists to reason clearly and critically. Clear
reasoning and critical thinking are exceptionally important
in our hobby. Probably the most vital component of animal
husbandry is the ability to "think" a problem through,
and then to rank and subsequently act upon the options that
result from that process. I have been writing my essays in
this column with the goal of providing assistance for such
attentive and reasoning reef aquarists.
The main thrust of my essays in this column
has been a discussion of the properties of the various animal
groups found in marine reef aquaria. Since its inception,
I have provided lists of the major characteristics of each
type of animal I have discussed and have expected that, with
a bit of reason and thought, most aquarists should be able
to use that information either to manage the care of desirable
organisms, or to eliminate undesirable ones. However, such
processes can only be done when aquarists are both thinking
clearly and have at their disposal valid and reasonable information.
Unfortunately, valid and reasonable data are exceptionally
hard to come by in this hobby, and thinking clearly doesn't
seem to found in overabundance, either. What information is
available is often hidden by obfuscation or comes from, at
best, questionable sources. These problems severely impact
the care of all of our animals.
I thought it would be useful to discuss
some of the ways in which we can try to cut through the fog
of misinformation and myth that surround this hobby. To some
extent, I will be following up on themes developed by Eric
and Rob, but this topic has been near and dear to my heart
for some time, as well. Basically, what I am attempting here
is to provide a series of suggestions, or "rules,"
that, if taken together, should provide some assistance in
cutting through this fog of aquarium myth, mysticism, and
just plain old "bull."
Gullible's Travels or a Little Knowledge is
a Dangerous Thing
One thing that is apparent to any reader
of the threads posted in online bulletin boards is the all-pervading
concept that every idea has equal value. In a real sense this
is probably due to the ultimately democratic nature of such
forums. Even with some control by moderators, basically anybody
can post anything about a given topic. As we know nothing
about any person posting, all of their ideas are accepted
as having equal merit. Unfortunately, in the big, beautiful,
real world, ideas do not all have equal value. Some are good.
Most aren't. The same ratio holds true in bulletin board threads.
Many of the posts are filled with either factual inaccuracy,
or repetition, or inanity or a truly delightful combination
of all three.
One of the most difficult things a person
has to learn to do is to be able to discriminate between good
and bad ideas. Throughout our lives most of the choices we
make are not life-or-death decisions. In our hobby, however,
making the wrong choice can result in the death of a lot of
beautiful animals, both directly and indirectly. So
How can we do better at the choices we make? Well, I will
discuss some rules to work with.
"He said, she said, who said, they said"
Reef keepers, especially those new to the
hobby, often assume that a lot is known about the organisms
that they are trying to keep. This is not often the case,
and as aquarists gain experience, they may gradually come
to realize this. Initially, a budding aquarist generally will
either take the word of the "instant expert" at
their local fish store, or they will purchase one or more
"reference" books to rely on. These books soon become
infused with the divine authority of a reef god, and are literally
treated as gospel. Unfortunately, most of the reef aquarium
books are dubious sources of information at best. Anybody
can publish one. Packaged in a pretty cover, it will sell.
It will sell regardless of the content. These books
are generally mixed compilations of lore, myth, and fact.
Unfortunately, in most cases it is very difficult to separate
the guess, from the fact, from the outright mistake.
One way to assign value to what you are
reading is to look for real data. Data are numbers or a series
of documented observations with some sort of statistical significance.
The reader needs to look for substantiation at every step
of the process. For example, when some aquarium author states
that such and such a species of coral grows in a given habitat,
you should ask yourself, first, "Who identified the coral?"
Second, you need to ask yourself, "Who documented it
in the habitat?" Third, you should ask, "how many
times was it identified and documented?" Once or twice
is just not enough to assign such "facts"as habitat
preferences. Corals are exceptionally easy to identify. Anybody
can put a name on one. Every aquarist can do this. Unfortunately,
virtually NO aquarist can do it reliably or accurately.
The real problem is not in identifying corals, but rather
it is in identifying them correctly. To do this well one needs
specialized training, specialized observational skills, observational
equipment such as microscopes, a library of references and
comparative specimens. Basically, one needs the resources
of a major research institution to be able to identify many
small polyped corals to any level below genus (See these columns
by Eric Borneman; Need
Help! Coral ID? Part I. Taxonomy of Stony Corals, Taxonomy
in the Reef Aquarium: A Simplified Guide to Basic Level Identification,
in Aquarium Corals: Part 3 - Everything Else - Soft Corals,
Zoanthids, and Corallimorpharians). A casual hobbyist
simply can't do it. Most aquarium authors can't either. They
have neither the background, nor the necessary references,
nor the necessary equipment. And if somebody needs a lab and
lots of references to do this, they are not going to be able
to do it "on the fly" as were, during a SCUBA dive
or from a photograph.
If a reference book shows a picture of
a given animal, and identifies it to species, do you automatically
believe the author? If so, why? I don't, unless I see some
sort of notation telling me who verified the identification
and what scientific or consulting institution they work for.
Even those scientists who identify animals as part of their
professional research need to have their work verified. I
know because, 1) I am a professional taxonomist, and 2) I
am often hired to verify the work of other taxonomists. At
other times, on other projects, a secondary taxonomist will
verify my work. So, when I see an aquarium photo guide listing
a lot of species, but listing no verifying authority, I take
anything I see in that book with a grain of salt; a small
grain of salt about 10 feet on a side.
Likewise, when you read about the requirements
of any animal, you should look for a citation to a reference
in a scientific journal (and not an aquarium reference) to
see where the information comes from. Then, if keeping the
animal is critical to you, you should go to a library and
examine that reference to verify that the author got the information
correctly. You will probably be pleasantly surprised when
you find that the author actually did get it right.
The most important thing to remember
is to develop a healthy dose of skepticism! Do not accept
information without documentation. And make sure the documentation
is from a reliable source. You DO need to verify sources,
and you should not automatically trust unsubstantiated references.
This skepticism should REALLY be directed
at advertisements. In our hobby, many vendors depend on hobbyist
ignorance to sell their products. Ignorance, fortunately,
is a condition cured by knowledge. For example, when you see
a statement like "replace what gets used up," you
should ask yourself the following question, "If substance
"X" gets used up, what happens to it and where does
it go?" The most fundamental natural law is the law of
conservation of matter and energy. Matter cannot be created
or destroyed, nor can one element be converted into another.
So, if you see a statement that some element is "used
up" in aquaria, just what does that statement mean? Ask
yourself, "How has it been used by organisms?" "Has
it been exported from the aquarium?" If it hasn't been
exported from the aquarium, it is still there, and it hasn't
been "used up;" rather it simply has been moved
from one place or form to another. Then you need to ask yourself,
where is the documentary evidence that any specific material
is used in any manner?
And your favorite reef book ain't the
place to go to find documentation!
Unless there have been experiments with
actual tests and measurements leading to published data, all
you have to go on is hearsay. And if all that hearsay is flouted
on advertising copy, then a prudent aquarist should keep their
wallet shut. Before you add anything to an aquarium containing
living animals, you need to know if what you are adding is
harmful or not, and then you need to know if it is necessary.
In very small amounts, most materials are harmless in aquaria,
but unless they are exported, they are continually cycled
and recycled between and within organisms. As more stuff is
added to the aquarium, materials can rapidly build up to levels
where they can cause problems, either as poisons or as excessive
nutrients. So, you should ask for some documentary evidence
that the material in question actually is necessary to the
well being of any organism.
|SCIENTIFIC JOURNALS CONTAINING
CORAL REEF INFORMATION:
BULLETIN OF MARINE SCIENCE
JOURNAL OF EXPERIMENTAL MARINE BIOLOGY AND ECOLOGY
MARINE ECOLOGY - PROGRESS SERIES
SCIENCE TEXTS OR REFERENCE
BOOKS ON REEFS:
Birkeland C. (ed.) Life and death of coral reefs. 1997.
Chapman & Hall, New York. 536 p.
Z. Dubinsky. ed. 1990. Ecosystems of the World: Coral Reefs. Elsevier Health Sciences, New York 550 pp.
Sorokin, Yuri I. 1993. Coral Reef Ecology. Springer-Verlag.
Berlin. (Ecological Studies, Vol. 102). 465 pp.
Some notes about the above, and other,
Trust, but verify
1) Most of these journals have websites that provide abstracts
or summaries of current and a variable number of archived
issues. These are generally searchable. That way, you can
even check from home to see if there are issues with articles
you are interested in reading without even making the trip
to the library.
2) Not all scientific articles or ideas have equal merit either.
However, all true and reputable scientific journals publish
articles that have been reviewed and examined by other scientists
familiar with either the animals, the techniques used, or
the system examined. This "peer review" does not
guarantee correctness or "good science," but it
significantly cuts down on the amount of grossly inaccurate
material for the reader, and while aspects of any article
may still be questioned, the degree of "incorrectness"
is not likely to kill animals in aquaria.
3) Specifically regarding the journal, Coral Reefs;
this is probably the best single source of information for
reef enthusiasts. All reef aquarium enthusiasts should become
members of the International
Society For Reef Studies. It is an exceptional bargain,
and supports coral reef science, conservation, and research,
and society membership includes subscriptions to both Reef
Encounters and Coral Reefs.
In other words, check the data. If you
are going to add something to your glass box containing several
hundred to several thousand dollars of livestock, don't you
think you ought to know what is in it? Take a look at the
side of your favorite bottle of "Reef Glop." If
it doesn't tell you what is in it, how do you know what is
in it and how much? If you don't know what is in it, how can
you make a reasoned choice as to whether or not, you should
add it? It gets even dicier; several additives have been chemically
analyzed and have been shown not to contain the materials
that the manufacturer claimed were on the label. (See Shimek,
2001; and online discussions).
So, how do you decide what to add to your
aquarium to promote the health of the organisms? Well, there
are really three choices. You can believe advertising hype,
or you can believe undocumented aquarium references, or you
can believe information from research documented in the scientific
Unfortunately, it is a lot easier to believe
the advertisements or the undocumented sources than to go
to a library and look up information in the scientific literature.
Upon such laziness and the subsequent residual ignorance is
virtually the entire business of aquarium additives and devices
TO DO A
SEARCH IN USING SCIENTIFIC DATA BASE:
GO TO A LARGE
LIBRARY; LARGE PUBLIC LIBRARIES OR UNIVERSITY LIBRARIES
GENERALLY CARRY "Biological Abstracts on Line"
also known as "BIOSIS"; THEY MAY HAVE OTHER
DATA BASES AS WELL.
1) Ask a librarian
to assist you for your first search. Generally, you
will be able to search several years' worth of publications
simultaneously from several thousand journals.
2) Try to limit your search. Searching on "coral,"
for example will give you several thousand citations.
Searching on "Acropora formosa" will
give you a lot fewer citations. Searching on Acropora
formosa, and habitat, will give you fewer yet.
3) Try to use several search items at once to narrow
4) After the search is complete, you will have a list
of many articles, often each will have a short summary
(called an "Abstract") of the article.
5) Each citation will list the pertinent facts about
each article, including the Journal that it was published
in, the volume, and the pages.
6) You then need to go to the stacks, or access it electronically
if the library has a subscription, and retrieve the
journal volume and read it.
7) If the library doesn't have the copy of the journal,
they may be able to obtain it for you, often for a small
fee, by Interlibrary Loan.
"When my cousin Vinnie added some marinara
sauce to his aquariums the corals did better
And just how was Vinnie able to tell? This
is an example of anecdote. Some folks would say "anecdotal
evidence;" however, there is no evidence with anecdote.
Anecdote is unsubstantiated or unverified observation generally
made by an unqualified observer who often really doesn't know
what they are looking at. One of the striking characteristics
of the reef aquarium hobby is the reliance on unsubstantiated
lore or myth, and its treatment as "God's own truth."
In fact, one of the oddities of this hobby is the preference
that most hobbyists seem to have for anecdote over documented
or scientific evidence. I think this preference for unsubstantiated
myth over documentary evidence is due to four factors. First,
many of the early references were written with a glib mix
of science and anecdote. This gave a lot of anecdotal beliefs
an unwarranted aura of believability. Second, while the ease
of communication with the internet allows the easy spread
of information, most really documentary data are still primarily
in print sources, not electronic ones. Consequently, the scientific
data that could be used to refute some of the wacky ideas
that float around the hobby are not easily accessible to the
average internet surfer. Third, most hobbyists simply don't
understand the difference between anecdote and experimentally
derived or determined data. Finally, many anecdotal procedures
or techniques are simple or promote simple clear-cut "cures"
to problems. For most folks, there is a profound appeal of
this simplicity over the real complexity of our aquaria and
the organisms we keep. It is easier to believe in and "understand"
a simple cure, even if it is wrong, than it is to believe
in the more complicated processes that may actually be occurring.
How is it possible to determine what is
anecdote and what is not? Basically, the hobbyist needs to
look for some sort of experimental documentation. Once the
experimental documentation is found, it should be evaluated.
This can be tough to do. Often it is tough to find the actual
numerical data, and then it can be difficult to understand.
Scientific data, whether it is observational or experimental,
is generally expressed, at least in part, with numbers. Unfortunately,
a large proportion of the reef aquarist population appears
to be uncomfortable with mathematics. Or at the very least,
it has been a long time since the individual has had to do
any real type of mathematical thinking.
Nonetheless, there are some things to consider
which can be used to separate anecdote from actual data. First,
one observation does not an experiment make. Look for duplication
or replication. Second, examine the data for controls and
experimental design. Most experiments are simplified as much
as possible. In essence, in doing experimental research, one
tries to only have one factor varying at any one time. All
other factors are kept as consistent as possible. It is fundamentally
impossible to have two biological systems that are identical.
Consequently, when organisms are used in biological experiments,
the goal is to try to get them as alike as possible, and use
statistical methodology to determine if the differences seen
in the experiments are real.
Our aquaria are just as difficult to deal
with as the natural world, and many of the caveats regarding
natural observation and experimentation are just as valid
in aquaria as in the real world. For example, one observation
of something in a tank is not enough to establish even a correlation
between two things. Furthermore, even strong correlations
do not say anything about causation. Our systems are multifactorial
in the extreme, and it is essentially impossible to do "controlled"
experiments in them, if that control is understood to mean
the type of controlled experiments possible in a simple laboratory
experiment. The typical hobbyist example of, "I added
"x" and my tank never looked better," is, plainly
and simply useless. It is patently impossible to determine
cause and effect from such an observation. Additionally, humans
are oriented toward visual stimuli to an extent that may be
without parallel in the animal kingdom. This means we tend
to judge everything by "how it looks." But, without
some independent framework of reference we don't know whether
or not to believe what we are seeing, or what it means, in
any case. Aquarists would do well to remember the aphorism
about books and covers; appearances are deceiving are not
There are lies, damn lies, and then, statistics.
The above statement, usually attributed
to Mark Twain, seems to sum up most people's attitude toward
statistics. In most cases, I think, hobbyists faced with trying
to understand some of the common statistics, simply choose
to ignore them or to ignore the articles altogether. Unfortunately,
this means that they lose out on a lot of the importance of
any articles containing statistics, and given that most scientific
research is validated with statistics, they miss out on the
importance of most research. However, it really is not important
to understand the basis for choosing a particular test or
how the test is performed. Generally, if the test is inappropriate,
it will not get published as the scientific journal editors
will require it to be correct before publication. This means
all a reef hobbyist has to do is examine the results and note
1) what is being tested and 2) the level of probability.
The levels of probability are often misunderstood.
The most frequently published probability is termed "alpha"
probability. This is the probability of choosing the wrong
answer given the data at hand. Alpha probability is generally
expressed as a small number, usually 0.05, 0.01, or 0.001,
and referred to as the "level of significance."
Usually, for results to be considered to be "statistically
significant," they must have an alpha level of 0.05 or
less. This means that the probability of finding the results
as given is less than 0.05 or one chance in twenty. Phrased
another way, if you perform a test that shows a difference
occurring with an alpha level of 0.05, you are 95% sure that
you would not get such results by random chance alone. The
lower the alpha levels, the greater the level of certainty,
so if the alpha level is 0.01, the level of certainty is 99%,
and so on. If you see numerical values, such as averages,
compared without a statistical analysis, do not put much reliance
on the those data unless the author makes a reasonable argument
as to why there is no statistical treatment.
You assume, WHAT?
Everybody makes assumptions, and those
assumptions then become part of their arguments and discussions.
Unfortunately, these assumptions are seldom clearly and explicitly
stated. It is important for readers of such discussions to
be aware of these assumptions, otherwise any statements that
are made will mean different things to different people. Some
of the assumptions that are made by aquarists are probably
harmless, such as the belief that vitamins defined by their
use in people will have beneficial effects in coral reef animals.
As ridiculous as this is, addition of low levels of human
vitamins probably have no long-term deleterious effects in
the treatment of our animals. Other assumptions are not so
benign. Many aquarists seem to believe that being in an aquarium
fundamentally changes the way these animals metabolize and
physiologically respond to problems. Such an assumption leads
to statements such as, "I don't need information about
what these animals do in the real world; I need to know how
to take care of them in my tank." The understood or,
better-stated, misunderstood, assumption here is that the
animal can somehow tell it is now in an aquarium and that
it changes its physiology accordingly. Animals cannot do this.
Wrongful assumptions such as this simply kill animals, and
are the basis of many of the inappropriate pieces of advice
that seem to be prevalent in the hobby. We all have assumptions
in our thought processes, but it is important to see that
such assumptions are grounded in reality.
Aquarists need to build up their skepticism
of unsubstantiated claims, unfounded anecdote and advertising
hype. As a group, we spend far too much time, money and effort
on unproductive and counterproductive efforts in aquarium
care. This misdirected and misguided effort directly effects
the well being of aquarium organisms and contributes to the
difficulties many aquarists have in keeping what are, fundamentally,
hardy organisms. If we can develop a series of rules and some
mental discipline, we should be able to ignore the ridiculous,
and concentrate our efforts toward the better care of our
boxes of water and their included critters.
My thanks to Eric Borneman and Rob Toonen for the inspiration for this essay, and to Eric Borneman and Skip Attix for their reviews which improved it.