Do Now Bacillus thuringienses (Bt) bacteria produce a natural insecticide (kills insects). Widespread use of Bt has lead to Bt resistance among insects. Why is this occurring? a) Individual insects that have mutations providing resistance to Bt can survive in the presence of Bt. The survivors pass this Bt resistance on to their offspring. b) Bt-resistant insects increase in the population by chance. There are so many insects that some of them are resistant to each type of insecticide. c) In the presence of Bt, individual insects evolve to become Bt resistant. d) Natural selection causes insects to generate genes providing resistance to Bt. ** choose and justify your answer**

Get back with your groups. You have 15 minutes to check in on your presentations. CHECK EACH OTHER. You present tomorrow! Presentations are due to me electronically by 7:30am tomorrow.

Topic: Natural selection Essential question: How do organisms change over time?

How do organisms change over time? several different mechanisms can produce change in organisms over time one of these mechanisms is natural selection natural selection is the process whereby organisms that are more adapted to their environment are more likely to survive and reproduce

how does natural selection work? individuals show variation in traits these variations are passed from parents to offspring (they are heritable) some individuals are more successful at surviving and reproducing than others individuals with favorable variations are more likely to survive and reproduce

how does natural selection work? individuals in this population of beetles vary in their color color is a heritable trait some beetles are more likely to survive and reproduce than others crows prefer to eat green beetles brown beetles specifically are more likely to survive and reproduce they pass on their brown color to their offspring over many generations, the population will consist of brown individuals University of California Museum of Paleontology's Understanding Evolution (http://evolution.berkeley.edu)

important terminology: brown beetles are more “fit” fitness is the ability of an individual to survive and reproduce in its environment “survival of the fittest”

important terminology: brown color is “adaptive” an adaptation is a trait or characteristic that increases the survival or reproduction of an individual relative to individuals without the trait

Galapagos finches: an example of natural selection in action Rosemary and Peter Grant and colleagues performed studies of finches on Daphne Major over many decades they have been able to witness natural selection in action

Galapagos finches medium ground finch (Geospiza fortis) eats seeds by cracking them with its beak the Grants measured bird size, beak size and what they were eating every year

there is variation in beak size in the population beak size is correlated with size of seeds the finch collects and eats: bigger beaks, bigger seeds

beak size is heritable big beaked parents have babies with big beaks small beaked parents have babies with small beaks

individual finches vary in their success at surviving and reproducing severe drought in 1977 caused plants to produce very few seeds, many finches starved to death and did not reproduce

survival and reproduction was correlated with having a large beak the most abundant seeds during the drought were large, hard seeds large seeds of Tribulus cistoides

survival and reproduction was correlated with having a large beak finches with large beaks were more likely to survive and reproduce

misconceptions about natural selection an individual does not change in response to natural selection the characteristics and make up of populations change in response to natural selection

misconceptions about natural selection natural selection is not forward looking there is no ideal end point to natural selection natural selection is not “perfect” organisms cannot be adapted to future environmental conditions

misconceptions about natural selection selection does not act for the good of the species if a trait increased the fitness of the group while reducing the individual’s fitness, it would strongly be selected against e.g. alarm calls by monkeys that warn the group but draw attention to the caller, causing it to get eaten

** choose and justify your answer** Bacillus thuringienses (Bt) bacteria produce a natural insecticide. Widespread use of Bt has lead to Bt resistance among insects. Why is this occurring? a) Individual insects that have mutations providing resistance to Bt can survive in the presence of Bt. The survivors pass this Bt resistance on to their offspring. b) Bt-resistant insects increase in the population by chance. There are so many insects that some of them are resistant to each type of insecticide. c) In the presence of Bt, individual insects evolve to become Bt resistant. d) Natural selection causes insects to generate genes providing resistance to Bt. ** choose and justify your answer**

Do Now Re-read your Natural selection notes from yesterday. Highlight key terms and ideas Write a summary at the bottom *I will be coming around to stamp this today*

Your grade on presentation 20 points possible 15 points from presentation above standard is extra credit I will be filling out the rubric as you do your presentation 5 points from your peer evaluation rubric number of points based on the distribution of work. Equal distribution, everyone gets 5 points. People who didn’t do their share get less than 5 points. People who did no work get 0 points.

2nd Presentations Columbia: http://prezi.com/r9m7c0cggyhy/edit/?auth_key=lqbtd2a&follow=5usok_zfweva Emory https://docs.google.com/a/apps.everettsd.org/presentation/d/1ZcyL1NYf2OUJ7MuiU--unJcgsQoAXMuoUKf-aq0Xaf8/edit?pli=1#slide=id.p Harvard https://www.youtube.com/watch?v=iQdgbeKfyCM MIT https://prezi.com/7ubx-21wv3tz/intro/?utm_campaign=share&utm_medium=copy Northwestern (ppt – Antibiotic resistance solution) Stanford (ppt – overprescription) UCLA: http://prezi.com/rpuzw_pxdkb_/edit/?auth_key=vyawflb&follow=jfkqe0n8fwju

3rd Presentations UCLA https://docs.google.com/a/apps.everettsd.org/presentation/d/1KT36dGG9tMueeMsR9V_Cd4vkzD_hHz4-Wtfi5fzi_rY/edit#slide=id.p Stanford https://docs.google.com/a/apps.everettsd.org/presentation/d/1_5PfiBcH-3Z-fIePy4yJfsBSxvULP9TJTIffGvYpnFc/edit#slide=id.p Northwestern: https://prezi.com/2vwqbl0jn1u3/antibiotic-use-in-agriculture/ MIT http://prezi.com/x7kzhcyl4lye/?utm_campaign=share&utm_medium Harvard https://docs.google.com/a/apps.everettsd.org/presentation/d/1ADBB4o_ZxWujxcAtIWI5LJW0IuvwEKcqBVsLMalyAQI/edit Emory https://docs.google.com/presentation/d/1SQRqmT2w9iNNwAnNYoybFY3RaywR3-nkXymoq5FWEg0/edit?usp=sharing_eid&invite=COLR2aMN&pli=1#slide=id.p Columbia https://docs.google.com/a/apps.everettsd.org/presentation/d/1Juf1PyEpELKuonNe9YADLwnMdBp-yEsdqw2LLiYnRRw/edit

6th Presentations Columbia https://docs.google.com/a/apps.everettsd.org/presentation/d/1mLpKW1KsmTE10xSlx-3rhqT6b_dHLLqudbjwGt7rtUM/edit?pli=1#slide=id.p UCLA http://prezi.com/bfysiuj3pewn/edit/?auth_key=rxlc7yl&follow=rocmxp6dteh7 Harvard Stanford https://prezi.com/2onp94g58m2u/antibiotic-presentation/?utm_campaign=share&utm_medium=copy MIT https://docs.google.com/presentation/d/1X4rduHzvjVkVs3w5yttRpIx5KzbRiEHCx6thGxn2D5A/edit?usp=sharing_eid&invite=CKCkvMIE&pli=1#slide=id.p Emory: http://prezi.com/nka9ibbkm-xe/edit/?auth_key=ec74ono&follow=8gn_fffgsltl Northwestern https://docs.google.com/a/apps.everettsd.org/presentation/d/13n0mfuf5PJGiqOeRJQzUNegJKcug0BSoV57rqx_6g0c/edit?pli=1#slide=id.g62ed40749_00

Quiz tomorrow! Bacteria Antibiotics Adaptations Variation Fitness Biotic potential (concepts, not math) Natural selection (after the quiz we will finish up the presentations)

Do Now What is the variation in this population? Why are some mice white and some grey? What is the selective pressure (what is causing the change in the population) in this example?