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DESCRIPTIONInsect Reproduction. Ch. 4 Introduction to Insect Biology and Diversity Tracey Anderson 12-01-2010. Reproductive Organs. Male Organs. Courtesy of Dr. Ken Hobson, University of Oklahoma . Reproductive Organs cont. . Female Organs. Courtesy of Dr. Ken Hobson, University of Oklahoma . - PowerPoint PPT Presentation
Insect ReproductionCh. 4 Introduction to Insect Biology and DiversityTracey Anderson 12-01-2010Male OrgansReproductive Organs
Courtesy of Dr. Ken Hobson, University of Oklahoma Female OrgansReproductive Organs cont.
Courtesy of Dr. Ken Hobson, University of Oklahoma Do the reproductive organs in insects resemble any other organisms?What about humans (Homo sapiens)? Reproductive Organs cont.
Courtesy of http://www.health-res.com/EX/07-27-22/internalfemalepelvic.jpg Courtesy of http://www.1cro.com/Diversity/malerepro_1.gif The Universe is not only queerer than we suppose, but queerer than we can suppose " J.B.S. HaldaneIt is not surprising that with the huge numbers of insects, evolution has produced many different reproductive avenues Oviparity Generally what is thought of when considering insect reproductionMost common formEggs are deposited after fertilization. Eggs nutrition comes from yolkUsed by most insect. Ex. Largest order of insect the beetles Types of ReproductionInformation in the next sections are from the textbook and courtesy of Dr. Ken Hobson, University of Oklahoma
Courtesy of http://denimpine.com/documents/pine_beetle_web1.jpgOvoviparity Fertilized egg is held in reproductive tract of female until completely developed Nutrition comes from yolk Used by some beetles and flies
Courtesy of Dr. Ken Hobson, Univ. of Oklahoma 7Viviparity Analogous to animal reproductionEgg held in female productive tract like ovoviparity but nourished by motherSome flies, aphids, earwigs, and some roaches
Courtesy of http://webdocs.cs.ualberta.ca/~games/aphid/gifs/aphids.gif
Courtesy of http://www.insectsofalberta.com/images/2006-apr-3_earwig.jpgParthenogenesis Production of progeny from unfertilized eggAsexual reproductionFavorable in constant environment which natural selection is not necessary to help increase fitnessProduction of males: bees waspsProduction of females: walking sticks Courtesy of http://www.animalpicturesarchive.com/animal/a7/New_Zealand_Walking_Stick-by_Tom_Pesendorfer.jpgPaedogenesis Unusual reproductive avenue used when resources are scareScarce resources caused larval ovaries to produce eggs which develop parthogenetically Midge flies
Courtesy of http://www.grahamowengallery.com/fishing/midge-2-large.jpgOffspring are genetically identical to parentThis is advantageous in a constant environment. Parent would be fit, so offspring would likely be fit, tooNatural selection would favor genetic diversity (sexual reproduction) in a changing environmentParthenogenesisBees (Order Hymenoptera) have a reproductive pattern known as Haplo-diploidy Females are produced normally with union of egg and spermMales are produced from unfertilized eggsMales would have 1 parent, 2 grandparents, 3 great-grandparents, 5 great-great-grandparents (interesting pattern, huh?)Parthenogenesis cont. It was once believed that the evolution of sociality in Hymenoptera was due to haplo-diploidy Females were more closely related to sisters than to offspringIt was thought that it was more advantageous to look after sisters than to reproduceRecently proven to be falseHaplo-Diploidy and the evolution of sociality