91短视频

Finding and catching salamanders might look like something 91短视频 senior Cerrie Mendoza would have done as a science-loving child, but in reality, amphibian hide-and-seek was just one aspect of her internship this summer.

Mendoza, a biology major from El Paso, Texas, is taking part in a collaboration pilot project between聽迟丑别听聽(NMNH), the , 91短视频 (91短视频) and James Madison University (JMU) to gather genetic samples from certain North American species of salamanders that were first collected and described 50 years ago. The project is funded by the .

In addition to finding and catching salamanders, Mendoza is learning research practices like DNA sequencing and publishing DNA barcodes, said , a NMNH molecular laboratory technician and one of Mendoza鈥檚 supervisors. 鈥淭his immerses Cerrie into the inner workings of many professionals in the museum, each conducting a variety of聽different methods to accomplish their jobs.鈥�

Exceptional experience

The placement is also giving Mendoza firsthand experience of the complexities of scientific research聽beyond what many interns undertake.

鈥淪he has to function as the project leader,鈥� said one of herinternship supervisors, . 鈥淪he has to actually think about and plan how to execute all of the steps. Many times, students at Cerrie鈥檚 level or age are simply functioning as lab or field techs which requires very little leadership or planning. For this project, however, Cerrie cannot just show up to work and wait to be told what to do. She has to figure all that out and then make it happen.鈥�

It鈥檚 not the first time Mendoza has figured something out and made it happen. She is attending 91短视频 because she wanted to 鈥渇ind my faith again鈥� and searched online for 鈥渟mall Christian universities.鈥� After visiting, she said, 鈥淚 fell absolutely in love with the campus, Harrisonburg, the Valley and Virginia. I wouldn鈥檛 want to go anywhere else.鈥�

In addition to many fun, new experiences (with healthy doses of 鈥淥ops,鈥� 鈥淲hat鈥檇 I just do?鈥� and 鈥淲as I supposed to do that?鈥� moments), Cerrie has also been reaffirmed in her belief that science 鈥� her favorite subject since grade school 鈥� is a vital pursuit: 鈥淚 love learning how nature and animals connect and respond to our environment and how they impact our world and how we impact theirs. We live in a cycled world where many things use one another in order to survive, and having that information for everyone to see is important.鈥�

Sequencing DNA

In her internship, Mendoza is adding data to the descriptions of certain salamander species found in Virginia.

When a new species 鈥� of salamander, for example 鈥� is found and described by scientists, it becomes 迟丑别听鈥済old standard鈥� against which all future comparisons of that species are made. In recent years scientists have begun including DNA evidence in the descriptions of these 鈥渢ype specimens,鈥� said , another of Mendoza鈥檚 mentors this summer and a research zoologist and curator of amphibians and reptiles in the NMNH .

In the past, though, DNA information was not known and so wasn鈥檛 included in type specimen descriptions. Mendoza and fellow intern Greg Steffensen of JMU are working to collect genetic samples from some of those same species of salamanders 鈥� in the exact locations where the original type specimens are from 鈥� to add to records.

Mendoza has contributed to the project by researching species in journal articles, planning species collection trips to efficiently include multiple sites, packing supplies and choosing campsites. She has helped to sequence the DNA from the collected samples and enter the sequences into the , and to curate those new specimens in the .

This kind of science can be thrilling for novice scientists, Mulcahy says 鈥� and he describes moments that could sound exciting even for the unscientifically minded who don鈥檛 understand the technical terminology: running 鈥� results on an agarose gel,鈥� seeing 鈥渂ands of DNA (exposed under ultraviolet light) for the first time,鈥� and 鈥渞ealizing they just amplified their first pieces of DNA.鈥�

And that鈥檚 not all, he says 鈥� because then they get 鈥渢hose sequence results back鈥� with 鈥渢he actual DNA copy of nucleotides, As, Ts, Gs, and Cs, all in a unique order for that individual. Then it鈥檚 exciting when they blast that sequence and find out how close it matches the representative specimens already in GenBank, 97%? 99%? Or is it not the species they thought it was?鈥�

鈥淏asically, this summer was a crash course in how to be a modern field biologist,鈥� Bell said of Mendoza鈥檚 experiences, and added that Mendoza鈥檚 internship is giving her much more than time with salamanders.

鈥淩egardless of whether Cerrie ends up working on Virginia salamander taxonomy in her future,鈥� she said, 鈥渟he now knows what it takes to organize a field expedition (including what to do when things don鈥檛 go exactly as planned), some important research techniques like DNA sequencing and the importance of taking detailed field notes, and maybe most importantly, she now has a whole team of mentors to support her in whatever she decides to do next!鈥�