Department of Biology Colloquium Seminar Series

Department of Biology Colloquium Seminar Series presents

Event Details

You are invited to attend a Biology Colloquium as follows:

The colloquium will feature Dr. Joe Ross and Biology Honors Student, Adrianna Grieco.

They will give a team presentation entitled, “Assessing Temperature Dependence of Developmental Delay Frequencies within Intra-species Hybrids of Caenorhabditis briggsae“.

Date:  Friday, October 27th

Time:  3:00-4:00 PM

Place: MCL 121

Note: If you need a disability-related accommodation or wheelchair access, please contact Maria Rochin at the Department of Biology at (559) 278-2001 or e-mail

Adrianna Grieco’s Biology Honors thesis abstract

Developmental delay is commonly seen in the F2 generations of Caenorhabditis briggsae temperate vs. tropical hybrid crosses. Specifically, the F2 hybrid offspring of tropical AF16 (from India) and temperate HK104 (from Japan) are known to produce developmental delay, which can be seen morphologically in the worms by examining their length and comparing the length to a wild-type individual. The genetic basis of this hybrid dysfunction is unknown, and an important step in eventually identifying the alleles involved is to determine whether the temperature at which the worms are grown influences the frequency of F2 hybrids that become delayed.

I measured the frequency of developmentally delayed individuals in an AF16 x HK104 hybrid cross grown at 20°C and compared the results to an AF16 x HK104 hybrid cross grown at 25°C. Results indicated that there was no statistical difference between the frequency of developmentally delayed F2 offspring after the trials. However, repeating this experiment with a greater number of trials could produce a more accurate statically significant value. Measuring the rate of developmental delay in C. briggsae aids in the understanding of the affects an increase of temperature, most likely global warming, can possibly have on the health of many organisms.”