PPT-MODES OF SPECIATION, CAUSES AND CONSEQUENCES OF EXTINCTION

Species A group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding Speciation It  is the  evolutionary  process by which populations evolve to become distinct . Evolution. Results of evolution. New species (speciation). Causes of evolution. Barriers between same species (gene pools). Geographical isolation -> leads to . allopatric. speciation. Temporal isolation -> leads to sympatric speciation. EVOLUTION #1 (Group 3). Strawberry Frogs Forever. Participants: Lin Xiang. Ingo . Schlupp. Tiffany Roberts. Anne . Grippo. Jerry Farris. Facilitators: Brooke . EXTINCT is FOREVER!!. Non-human causes of extinction:. Volcanic events. Ocean temperature change. Sea level changes. Meteorites. Glaciations. Global climate change. Competition/predation. Human causes of extinction/loss of biodiversity - HIPPO. Evolution. Speciation Basics. Individuals of different species cannot . interbreed. under natural conditions . Described as being . reproductively isolated . from one another. Populations of different species do . Brian O. ’. Meara. EEB464 Fall . 2015. http://www.youtube.com/watch?v=lopTMhAbXoI. Initiation of speciation. Maintenance of current species. Prezygotic. Postzygotic. Zygote image © Laboratoire de Biologie de la Reproduction; Lausanne, image downloaded from . The rise and fall of biodiversity. Four major mass extinctions of marine organisms:. End of Silurian Devonian, Permian, and Cretaceous). Rise in diversity during Cambrian, Silurian, Cretaceous, and Paleogene. Concept 22.2: Speciation can take place with or without geographic separation. Speciation can occur in two ways. Allopatric speciation. Sympatric speciation. Allopatric (. “. Other Country. ”. ) Speciation. Meara. EEB464 Fall . 2017. http://www.youtube.com/watch?v=lopTMhAbXoI. Learning objectives. Understand factors that can lead to speciation. Consider the geography of speciation. Describe approaches to . Species. == “kind” or “type” in Latin. Typological . (morphological) species. . == a group of organisms that share certain characteristics which are different than other groups—usually differences in anatomy. . Species. – group of organisms that interbreed and produce fertile offspring. Subspecies. – groups that are on the way to being separate species; have started being genetically different. Individuals in the same species share a common gene pool. Remember. Operant conditioning extinction differs from classical conditioning extinction. During extinction, responding decreases to baseline levels for both classical and operant conditioning. BUT: Operantly conditioned behavior shows:. Essential Questions. What is extinction?. Which species have become extinct in modern times? . What are the characteristics of past mass extinctions? . How do modern extinction rates compare with natural (background) rates?. (Unit 10, species concept. Sympatric speciation . Sympatric speciation, (from the Greek ‘same place’) involves the splitting of an ancestral species into two or more reproductively isolated groups without geographical isolation of those groups.. Avneet. Singh, Steven . Ancheta. , Giovanni . Corralhejo. , Katie . Laackmann. Definition. Origin of new species in evolution. There are two general modes of speciation. Allopatric. speciation. Sympatric speciation.