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Marta Martínez Wells, Research Scientist (Ph.D., Connecticut)

Contact Information:

Dr. Marta Martínez Wells
Department of Ecology and Evolutionary Biology
University of Connecticut
75 N. Eagleville Road, U-43
Storrs, CT 06269-3043
Tel: (860) 486-3947/4550
Fax: (860) 486-6364

At Yale, where I am currently a lecturer, contact
I also have a website at Yale, where you can find additional information.

Current Areas of Research:

Evolutionary Biology, molecular evolution, speciation on green lacewings (Neuroptera), courtship song behavior.

For the past 10 years I have been working with Charles Henry on green lacewings (Neuroptera, Chrysopidae). We are interested in understanding the role of mating signals in reproductive isolation among cryptic species of insects. Even though, it is not clear whether the changes in courtship song features precede, induce, or develop after speciation, courtship songs become a very important factor in the process of speciation, because they result in the formation of swarms of sibling species distinguished only by differences in their songs.
Green lacewings of the order Neuroptera, are a good case study to look at the role of courtship songs in reproductive isolation and at evolutionary changes in song features among closely related species.
Male and female green lacewings establish duetting behavior through a low frequency tremulation courtship song, that always precedes copulation. If you would like to hear what these vibrational signals sound like, click HERE. A combination of playback experiments, laboratory hybridization, electrophoretic and mitochondrial DNA studies has shown that many species of green lacewings are really groups of cryptic sibling biological species previously unknown.
In organisms that use acoustic signals, there are some features that are used in species recognition. In many insects, it has been shown that the temporal features of songs such as pulse rate or inter-chirp interval play a key role on species recognition. In Chrysoperla plorabunda, the temporal features of the courtship song (volley duration and interval) seem to be very important features to elicit duetting responses in females.
The process of speciation must frequently involve the evolution of novel signals and preferences and the problem is to understand how this occurs. Data on behavioral responses of hybrid green lacewings to both hybrid and parental songs, suggest that the mechanisms of production and reception of songs may be coupled. Then, changes on song features during speciation could be accompanied by changes in the receiver's signal, allowing for populations to diverge through assortative mating.
Currently, I am doing a study using mitochondrial and nuclear DNA sequence data, in Chris Simon's Laboratory, to reconstruct the phylogenetic relationships among several closely related species within the genus Chrysoperla. The objective is to enhance the understanding of the evolution of courtship songs, and try to clarify the relationship between song divergence and rapid speciation within certain of its species lineages, such as the C. plorabunda complex, C. downesi complex and C. carnea complex. Some of the preliminary results show the song species within each complex as being more close related to each other than to any other species in the other complexes. This results agree with the prediction that if speciation trough song divergence is the evolutionary process occurring in these insects, the song species should be sister taxa within each complex.

 Selected Publications:

Henry, C. S., and M. M. Wells. 1990. Geographical variation in the song of Chrysoperla plorabunda (Neuroptera: Chrysopidae) in North America. Ann. Entomol. Soc. Amer. 83:317-325.

Wells, M. M. and C. S. Henry. 1992a. The role of courtship songs in reproductive isolation among populations of green lacewings of the genusChrysoperla (Neuroptera: Chrysopidae). Evolution 46(1): 31-42.

Wells, M. M. and C. S. Henry. 1992b. Behavioral responses of green lacewings (Neuroptera: Chrysopidae: Chrysoperla) to synthetic mating songs. Anim.Behav. 44:641-652.

Henry, C. S., M. M. Wells, and R. J. Pupedis. 1993. Hidden taxonomic diversity within Chrysoperla plorabunda (Neuroptera: Chrysopidae): two new species based on courtship songs. Ann. Entomol. Soc. Am 86:1-13.

Wells, M. M. 1993. Laboratory hybridization in green lacewings (Neuroptera: Chrysopidae: Chrysoperla): evidence for genetic incompatibility. Can. J.Zool. 71:233-237

Wells, M. M. and C. S. Henry. 1994. Behavioral responses of hybrid lacewings (Neuroptera; Chrysopidae) to courtship songs. J. Insect Behav. 7:649-662.

Wells, M. M. 1994. Small genetic distances among populations of green lacewings of the genus Chrysoperla (Neuroptera: Chrysopidae): implications for speciation. Ann. Entomol. Soc. Amer. 87(6):737-744.

Wells, M. M. and C. S. Henry. 1998. Songs, reproductive isolation and speciation in cryptic species of insects: a case study using green lacewings.  Pp. 217- 233 in: D. Howard, ed. Endless Forms: Species and Speciation. (n/a), Oxford, New York.

Henry, C., M. Wells, and C. Simon.  1999.  Convergent evolution of courtship songs among cryptic species of the carnea-group of green lacewings (Neuroptera:  Chrysopidae: Chrysoperla).  Evolution 53(4):1165-1179.
Henry, C.S., Wells, M.L.M. & Holsinger, K.E. (2002) The inheritance of mating song in two cryptic, sibling lacewing species (Neuroptera: Chrysopidae: Chrysoperla). Genetica, 116, 269-289.

Henry, C.S. & Wells, M.L.M. (2004) Adaptation or random change? The evolutionary response of songs to substrate properties in lacewings (Neuroptera: Chrysopidae: Chrysoperla). Animal Behaviour, 68, 879-895.

Courses Taught: Evolution, General Ecology, Introductory Biology, Biology of Terrestrial Arthropods, Animal Behavior, Laboratory on Evolutionary Biology, Diversity of Life.

 Collaborators: Charles Henry, Chris Simon