What is that "we" incompatibilists are talking about?

Before I continue with writing about species, I would like to address very concisely something that pops up every few weeks or so in a part of the blogosphere that I read: the controversy over determinism and free will. The occasion is a recent post by Jerry Coyne, who linked to a study showing that certain decisions are made unconsciously several seconds before we become conscious of them to argue that, and the following word is where the crux lies, "we" do not really make any decisions at all:

The implications of this research are obvious: by the time we’re conscious of having made a “choice”, that choice has already been made for us—by our genes and our environments—and the consciousness is merely reporting something determined beforehand in the brain.

To summarize the determinism vs free will issue, there are three main positions. The first is held by many religious believers, Cartesian dualists, people with an esoteric bend etc. They believe that in addition to the material world following its physical rules there are souls or spirits or whatever immaterial components to our mind (for the sake of simplicity I will subsequently simply speak of souls), and that those souls are somehow transcending the cause-and-effect of the material world.

Botany picture #51: Cardamine pratensis

Cardamine pratensis (Brassicaceae), Germany, 2008. I am not overly fond of Brassicaceae. Although the family is economically very useful - cabbage, broccoli, rapeseed, radish) - and provides with Arabidopsis thaliana the most important model organism from the plant kingdom, their flowers are pretty boring, and they are one of those families that are generally hard to identify without fruits. In addition I unfortunately hate cabbage with the exception of red kraut. The spring flowering species above I always found quite attractive though.

Tidbinbilla

We made a family trip to Tidbinbilla Nature Reserve today. It is a superb destination for a day trip from Canberra, especially if you are interested in seeing wildlife.

Part of the Nature Discovery Playground; several barbecues are available at the site, and it was quite full with families having lunch.

Hanging Rock peeking out of the Eucalyptus forest. Yes, the rock is as big as it looks next to that tree.

I have never before seen so many turtles as today at the Sanctuary wetlands of Tidbinbilla. They were constantly popping up to take air, then diving back in. Some of them looked at us curiously as if they were expecting to be fed, however.

And another cute little reptile! Presumably a red-bellied black snake?

Finally, something botanical: a frond of Pteridium esculentum, the native bracken, breaking through the bitumen of a footpath. Unfortunately, most of the plants that were in flower were introduced weeds. Autumn is really starting here.

Classifying the species concepts

This post continues a series on species that began with this introduction.

So looking over the literature and the aforementioned list of 26 species concepts, let's try to classify the concepts into different groups:

Synchronous concepts
    Reproductive community concepts
            *Compilospecies
        Biological species
        Cohesion species
        Genetic species
        Genic species (?)
        Recognition species
        Reproductive competition species
    Phenetic and cluster concepts
        Autapomorphic species
        Ecospecies
        Genotypic cluster
            *Agamospecies
        Morphospecies or typological species
        Phenospecies
    Phylogenetic concepts
        Phylogenetic species
        Genealogical concordance species
Asynchronous concepts
    Internodal species
    Composite species
        *Successional species
Incertae sedis
    Evolutionary species

The first division, indicated by bold font, is whether the concepts deal only with species in the here and now or, more generally speaking, with those existing together in one time-slice (synchronous) or whether they have a historical dimension (asynchronous). Note that the latter are rarely of interest for anything beyond theoretical discussion unless we are talking about a group with an excellent continuous fossil record. I am not sure where to place the Evolutionary Species Concept because I may not quite understand it. It sounds a bit like a reproductive community seen from an asynchronous perspective, so I have placed it apart for the moment. (Similarly, I previously understood the genic species to mean something different from how it is described in the list I linked to, so there is a question mark behind it.)

Within the synchronous concepts that deal with delimiting and circumscribing species in the present we have a second division, indicated in italics, where the concepts are grouped by their main grouping and, if defined, ranking criteria. The first group is what we might call the family of the biological species concept, different concepts that attempt to delimit species by the ability or propensity of individual organisms to interbreed. The second group defines species via some kind of character combination or overall similarity. In all these cases, species are groups of individuals that are ecologically, morphologically or genetically more similar to each other than they are to individuals belonging to any other species. In contrast to this essentially phenetic approach, the small third group employs some kind of phylogenetic approach to species circumscription.

I have left out several concepts that are silly or too similar to others. The ones that are further indented and marked with asterisks are also a bit dubious as they appear to represent merely special cases of the concepts directly above them. Even having reduced the number already, it will still be useful to lump them further and discuss, for example, all reproductive community concepts together. On the other hand, it appears useful to take a more granular approach to the phenetic concepts - but that may just reflect my personal biases.

Botany picture #50: Eryngium campestre

Eryngium campestre (Apiaceae), Germany, 2007. The Apiaceae are best known for the carrot and all the spices they provide - fennel, parsley, caraway, anise, etc. - and most of them look kind of the same: deeply divided leaves and small usually white or sometimes yellow flowers arranged in a double umbel. But there are a few more unusual groups that a beginner in botany would not even recognize as part of the family. The genus Eryngium is one of those - many of them look more like thistles, and the South American representatives look much like monocots. Unfortunately I do not have good pictures of the latter, so here is a European representative.

Species (introduction)

We encounter species all the time when reading about biology. Darwin titled his most important work The Origin of Species. Articles about groups of plants or animals boast how many species they contain compared to other groups at the same rank of a classification ("this is the largest order of insects", etc.). Likewise, you can find information on how many species occur in this country as opposed to that. Some species are considered threatened and protected by law, and conservationists design species recovery plans to protect species from extinction. Evolutionary biologists calculate speciation and extinction rates for different groups of organisms, i.e. rates at which species appeared and went extinct in evolutionary history.

Given all that, it may come as a surprise that a good number of biologists would not consider species to actually, you know, exist.

Some time ago a colleague asked that question in our journal club over at the university: everybody here, do you think that species are real? Meaning, are species entities that actually exist out there in nature and that we can reproducibly and objectively discover, or are they merely arbitrary human constructs? And quite a few colleagues answered no, species don't have any (special) reality. My own reaction was to stall. I think it depends on the group of organisms you are talking about, was what I said.

That was then, and since then I have given the topic a lot more thought, which is why I want to write about it in the next few posts (exempting the usual botany pictures and whatever else may come up). I am certainly not an expert on the theory but as a taxonomist I need to deal with species all the time. I also do this in part to order my thoughts in preparation for some teaching I expect to be involved in later in the year.

Botany picture #49: Bomarea angustipetala

Bomarea angustipetala (Alstroemeriaceae), a twining petaloid monocot from the Colombian paramo of Chingaza, 2007. I really should read up on the current systematics of petaloid monocots one of these days.