Archive for April, 2009
A new blog just sprung into life. Macromite’s Blog:
I spend last Thursday and Friday attending a conference held at the University of Lisbon: Evolution today and tomorrow: Darwin evaluated by contemporary evolutionary and philosophical theories. 23 – 24 April 2009. Don’t let the event’s webpage design fool you, the conference was well organized and brought together a diverse array of interesting speakers, both Portuguese and from abroad. › Continue reading
There is a skirmish going on at Dechronization blog right now1. This is a coauthored blog about phylogenetics. I like used to like this blog (its was right there on my blogroll —->2). There are surprisingly very few blogs about phylogenetic methods these days, despite the wide use that phylogenies currently have in evolutionary biology and beyond (e.g., linguistics). I will complain that, for nine authors, they post little, sometimes not a single post during a month.
- 1. Update 12:00pm GMT, April 22nd, 2009. Original post on Dechronization deleted.
1.2. Update, May 2nd, 2009. It seems that the original poster did not agree with the removal of his posts and reposted the Dechronization announcement of the Cladistics Workshop here. ↩
- Update April 23nd, 2009. I took the link out of my blogroll to show a dear friend that I care more about him than a silly blog. ↩
This image shows the mouthparts of a trap-jaw ant in resting position. The only structures really visible are the prominent elongated mandibles (in yellow) that project forward. The rest of the pieces, laying immediately below, are retracted inside the preoral cavity.
In the preface of his 1956 classic Anatomy of the Honey Bee1 the great American entomologist Robert E. Snodgrass explains the book’s title:
First, it must be explained why the name of the bee appears in the title as two words, though “honeybee” is the customary form in the literature of apiculture. Regardless of dictionaries, we have in entomology a rule for insect common names that can be followed. It says: If the insect is what its name implies, write the two words separately; otherwise run them together. Thus we have such names as house fly, blow fly, and robber fly contrasted with dragonfly, caddicefly, and butterfly, because the latter are not flies, just as an aphislion is not a lion and a silverfish is not a fish. The honey bee is an insect and is pre-eminently a bee; “honeybee” is equivalent to “Johnsmith.” [vii]
- Snodgrass, R. E. 1956. Anatomy of the Honey Bee. Cornell University Press. Ithaca, New York. ↩
The metapleural gland is the definitive character of ants. It is unique to the family. Nothing homologous or similar is found anywhere else in insects. Within the tree of life of Hymenoptera, myrmecologists agree that the appearance of this gland provides a good cutting point to marks-out ants as a monophyletic group1. You have it? You are an ant. You don’t? Sorry, you don’t qualify, get the hell out of here lousy wasp2. It is the ultimate ant synapomorphy.
- Grimaldi, D. and D. Agosti (2000). The Oldest Ants are Cretaceous, Not Eocene: Comment. Canadian Entomologist 132(5):691-693. ↩
- Yes, one can insult insects by calling them members of the Order Phthiraptera ↩
Last week I posted my Homology Weekly as an April’s fool joke attempt. Since I am sure I was the only one to found it somewhat funny (and looking back, barely so), I decided to make for it this week and post something really interesting for my readers and especially eye-candy for my myrmecologist colleagues. It will be ready to go tonight, provided I have some time to work after supper, but no later than tomorrow.
In my defense I have to say that nothing I wrote in that post about DNA sequences was false. It was meant as a parody/criticism of the level of reductionism that results from our practice of treating each single nucleotide position as a character for phylogenetic reconstruction equivalent to a complex morphological structure.
This is an excellent example of the way systematic papers should be. In the latest issue of the Proceedings of the National Academy of Sciences (USA), Blackledge and coworkers assembled a comprehensive data set for cladistic analysis of orb web spiders that includes six different molecular loci, 143 morphological characters and behavior in the form of characters derived from web architecture.
At any given position along their DNA sequences, ants may have any of the following four nucleic acid types: A, T, C or G. Unless we are dealing with the mitochondrial genome that is known to have quite a few A+T-rich regions in insects, in which case expect to find just those two types of nucleotides.
- Tom Waits