Week 07 - C. elegans TEST environment

  due date: Tue Feb 28 by 9:00 PM
  email to: mcb419@gmail.com
  subject: hw07
  email contents:
    1) jsbin.com link to your EVOLVE code (not to this file)
    2) copy and paste your entire RESULTS TABLE into the email
    3) answer all the questions at the bottom of this page in the email
  

In this assignment you will evolve and test chemotaxis controllers for C. elegans. Start by following the instructions in the C. elegans EVOLVE environment. Once your EVOLVE code is working properly, you will need to copy the version of Bot.prototype.genetic that you developed there into the appropriate place at the top of this jsbin project. The rest of the bot code has been provided in a library gaWorm.js, which you will not need to modify.

TEST Instructions

Results Table

ControllerGenesPeakFitness
mean (std dev)

Questions

*** Please answer the following questions in the body of your email when you submit your assignment.***

  1. Gene 0 controls the time constant for the low-pass neuron. What's the typical range of values of gene 0? Try changing this value manually in one of your evolved gene string. What happens if you make it very small (-9)? What happens if you make it relatively large (9)?
  2. What is the typical relationship between genes[1] and genes[2]? What are these first two terms of the weighted sum computing?
  3. The last line of the controller code constrains the change in heading direction to be between 0 and 0.2 radians per tick. For what range of weighted sum values would the change in heading be zero? How does this relate to the "run" phase in bacterial run-tumble behavior?
  4. For what values of the weighted sum does the worm turn at its maximum rate? How does this turning behavior relate to the "tumble" phase of bacterial run-tumble behavior?
  5. How would you characterize this evolved control strategy in terms of the various types of kinesis and taxis strategies that we have discussed previously?
  6. (Optional) Feel free to comment on anything else that you found interesting, or confusing, or describe any additional experimental tests that you made.