I'm pleased to be able to post some photos taken on a visit to Dartmouth College, where I spent the day with Laurel Symes, a PhD candidate.  She is doing research on speciation - and she is focusing on the SubFamily of Oecanthinae to gather data.  Laurel gave me a tour of the equipment she is using to extract minute amounts of tree cricket DNA to be analyzed -- and a good number of steps in between.   A more detailed explanation is posted below these photos.

These tiny plastic vials contain selected parts from adult tree crickets and are awaiting further processing. 

This is a Spectral Analyzer.  This is the machine that gives the DNA sequence results.

This is Laurel explaining the process involved in carrying out her research.

Here is a synopsis of Laurel's research:  One application of DNA sequencing is determining the relationships among species. Similar to the genetic paternity tests used to determine the relatedness of people, DNA sequencing can be used to determine the relatedness of species. 

 There are two major steps to determining the relationships between species. The first step is to obtain short (or long) DNA sequences from the species that you are interested in. The following tutorial provides a nice overview of how you obtain and sequence DNA: http://www.wiley.com/college/pratt/0471393878/student/animations/dna_sequencing/index.html.

The second step is to use the resulting DNA sequences and a set of computer programs to determine how similar the sequences are. Given that all organisms share a common ancestor, species that diverged more recently should have gene sequences that are more similar. By comparing the similarities and differences among sequences for all of the species that you are interested in, it is possible to build a phylogenetic tree—a diagram showing how species are related. The following website provides additional details on building and interpreting phylogenetic trees: http://evolution.berkeley.edu/evolibrary/article/phylogenetics_01

A LARGE NUMBER OF SCIENTIFIC PAPERS CAN BE ACCESSED VIA THE SINGING INSECTS OF NORTH AMERICA [ SINA ] WEBSITE:  REFERENCES

Acoustic Communication -  North Carolina State University

Preferred males are not always good providers: female choice and male investment in tree crickets Luc F. Bussière, Hassaan Abdul Basit and Darryl T. Gwynne 

Forrest, T.G. 1982. Acoustical communication and baffling behaviors of crickets. Florida Entomologist 65: 33-44.                                                                                                               http://facstaff.unca.edu/tforrest/publications.html              

Sismondo E. 1979. Stridulation and tegminal resonance in the tree cricket Oecanthus nigricornis (Orthoptera: Gryllidae: Oecanthinae). J. Comp. Physiol. 129: 269-279.

Temporal Rhythms in the Signals of Insects -- Univ of North Carolina - Asheville    http://facstaff.unca.edu/tforrest/ASA%2098%20Seattle/sld001.htm

Post-Copulatory Behavior of the Two-Spotted Tree Cricket, Neoxabea Bipunctata
Author: T. J. Walker
Publisher: Florida Entomologist, v. 61, n. 1, p. 39-40                                                           Click here

Photos of Insect Collections at major institutions

California Academy of Sciences

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