Down and Dirty in the Desert


Today’s experiments consisted oftesting for life in soil crusts, extraction of chlorophyll from soil, andcreation of a mud battery. 

In testing for life in soil crusts weprepared three sets of solutions as follows:

Crust+ Indigo Carmine Blue (Dye)+ LBmedia

Pavement+ Dye+ LB media

Sand+ Dye+ LB media


Crust + Dye

Pavement + Dye


AND one Control of:            Dye+LB media 

Crust refers to the soil samples wecollected that contained biological crusts, pavement refers to soil samplescollected in the same area that did not contain any visible life, and sandrefers to a sample collected from the Kelso sand dunes.      

The experiment was set up in nine testtubes.  Every two hours we are measuringabsorption using a spectrophotometer. The test for life uses a color changing redox reaction between the dyeand sugars found in the solution. No color change has been noticed yet, but thesolutions will continue to incubate over night and more accurate observationswill be made later. 

Chlorophyll extraction posed thequestion: “What type of chlorophyll do biological soil crusts contain?”   The process of extraction used 3mLethanol with 1.5g crust.  It wasplaced in the oven at 70 Celsius for 5 minutes.  It was then placed in mixing until cool for 45 minutes.  UV/Vis scan measured between240-800nm.  The resulting spectrumresults suggested the presence of mixture of chlorophyll A, chlorophyll B and possiblyβ-carotine.

The mud battery will be used in theoasis lake on the Zzyzx property. Its components include a mat of 3000 micro threads bulks of carbonfibers.  Each bulk of thread wasthen weaved with copper wire.  Onelong piece will be put in the water under the ground of the lake in order forcyanobacteria to grow.  Another pieceof carbon fibers weaved with copper wire will be put above the ground whichwill be a conductor of energy. Four long thick pieces of graphite are then partially insulated withcopper.  This will serve as anotherconductor out of the water and into the battery.  There is also a switch which we fabricated in order tocontrol amount of resistance and to turn circuits on and off.   The battery will act as a prototype for a possible batterysource deep in the ocean to power deep ocean probes where there are no otherpossible energy sources (i.e. geothermal vents, currents, or sunlight)available to run the probes on.

Tonight’spresentation was titled, Scotch on theRocks, by Keith Evan Schubert, Jane and Ernesto. Biological soil crusts arecolonies of different organisms cooperating together to survive in theirenvironment.  In order for theseorganisms to survive successfully in their environment, they often grow indistinct patterns. These patterns are often the same linear or circularpatterns; a pattern of life as it forms groups in an environment.  The formation of these patterned designscan be very intricate.  The shapeof these microbial communities can potentially reveal information about whatenvironmental factors are most important to life in their ecosystem.

            Complexmathematical models have been developed in the attempts to explain the patternsof growth given certain biological parameters. The limitation of these modelsis that they are impractical for field use since the parameters are difficultto alter. A simpler, binary system of analyzing pattern growth.  Using a program of General CellularAutomation, a set of rules can be inputted to determine which patches of growthwould stay alive or die after the next time interval. This simple interfacewould allow scientists to simulate how growth patterns would look given acertain set of parameters. Another technique would be to take a series ofphotos and look at the photos in a time lapsed manner to observe the growthusing the rules above.  These ideasconverge to all propose real life simulation of growing patterns and theinteresting part of this foundation is that it could be configured vice versa. Dependingon the complexity of the parameters, it might be possible to determine theoriginal configuration of the growth based on what it looks like now. GeneralCellular Automation presents exiting possibilities for applications in areas ofstudy as varied as tsunami damage prediction to identifying possible sites forextraterrestrial life.

Astrobiology Relation

-There could be apresence of chlorophyll in deep, inaccessible soil crusts of other planets.

-Discovering thecauses for patterns in microbial growth could help scientists determine goodplaces to look for extraterrestrial life. 

The Mathematical Perspective

Asa mathematics major participating in this program, this entire experience hasbeen a whirlwind. It seems as if I am introduced into a new topic every hour.Though this is overwhelming at times, it is possible to introduce these topicsinto a math classroom. From the brainstorming that has taken place among themath majors here, it seems the best integration of these concepts would bethrough word problems. Students could be directed to find volumes, growthrates, and heights. We could also work to integrate the group based learningthat was taking place in the lab. By redirecting the classic lecture based mathclass into small group work, it’s easy to see how students could facilitatetheir own learning successfully.

Lesson Ideas

-Give power pointthat is an understanding of concepts, but with pictures not notes!  This would be best to execute anunderstandable presentation where you talk and students listen and look, notread.  This would be anintroduction to patterning of organisms.    .             

-Use of General Cellular Automation in the classroom allows students toexplore the, “why does doing this make that?” question.   Students are given the chance to set their own rules thatdetermine patterns of growth.