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Douglas H Erwin - 2014 Venice ECLT Meeting
Douglas H Erwinn - 2014 Venice ECLT Meeting
Insite Project
May 05, 2014
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54 slides
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2014 Venice ECLT Innova3on Mee3ng Douglas H Erwin
Dept of Paleobiology Na3onal Museum of Natural History -
Defining Novelty • Are ‘novelty’ and ‘innova3on’ synonymous?
• Character based: new construc+on elements of a body plan (not homologous to pre-‐exis+ng structure) • Process based: novelty should involve a transi+on between adap+ve peaks and a breakdown of ancestral developmental constraints so that new sorts of varia+on are generated (Halgrimsson et a. 2012 J. Exp. Zool) -
From Erwin and Valen3ne (2013) The Cambrian Explosion Fundamental
Ques3on: What mechanisms led to the evolu3on of Opabinia, and have they changed over 3me? -
Search Vs Construc3on • Innova3on is oUen described as
search through a space of “the adjacent possible” (Kaufmann, Wagner) -
Search Vs Construc3on • Innova3on is oUen described as
search through a space of “the adjacent possible” (Kaufmann, Wagner) • This is only the appropriate metaphor in which the underlying network dynamics are rela3vely simple • If the network is complex, constructed from the interac3on of agents, than search is not the appropriate metaphor -
Search Vs Construc3on • Ques3on: Do the processes and
mechanisms of innova+on differ in networks dominated by search rather than construc+on? -
Adaptive Radiation of Hawaiian Silverswords All photos from Hawaiian Silversword
Alliance website Carlquis+a California Argyroxiphium sandwicense ssp. macrocephalum Dubau+a waialealae Dubau+a la+fola Dubau+a re+culata -
Adaptive Radiations and Opportunity • Appearance of new resources
• Ex3nc3on of species previously exploi3ng resources • Coloniza3on of new areas • Evolu3on of a new trait (“key innova3on”) -
Characteristics of the Cambrian Explosion • High morphologic disparity
• Rapid appearance of crown group bilaterians • Expansion of ecological networks • Puta3ve link to increased oxygen in marine environments • The Cambrian explosion represents the construc3on of a design space -
Monosiga Amphimedon Trichoplax Nematostella Drosophila genome size (Mb) 41.6 167
98 450 180 # genes 9,100 ? 11,514 18,000 14,601 # cell types 1 12 4 20 50 # T.F.’s ? 57 35 min. 87 min. 87 # T.F. families 5 6? 9 10 10 microRNA 0 8 0 40 152 Genomic Complexity (Erwin, 2009; Erwin & Valentine 2013)" -
Nature of Kernels • Recursively wired regulatory genes
• Specify the spa3al domain of a part of the developing embryo, oUen a regional pabern • The kernels are dedicated to development and are not re-‐used elsewhere • Interference with the func3on of any gene will destroy kernel func3on • This forces subsequent evolu3onary change either upstream or downstream of the kernel -
Implications • There is a structure to the network
of developmental regulatory interac3ons • Changes in some parts of regulatory networks are easier than in others • Some types of changes, par3cularly the establishment of kernels, appears to have been easier early in metazoan evolu3on; these kernels are now highly refractory to modifica3on -
Origin of Eumetazoa Origin of Developmental Toolkit
Increase in miRNA families; complexity of dGRN interac3ons Most signalling pathways present -
• Inven+on is the crea3on of something new and
dis3nct (contrast with varia3on on established themes) • Innova+on occurs when inven3ons become economically or ecologically significant Invention & Innovation Joseph Schumpeter (1883-1950 -
How are new evolutionary spaces created? • Poten+ated by broader
environmental segng (physical, gene3c, ecologic) -
How are new evolutionary spaces created? • Poten+ated by broader
environmental segng (physical, gene3c, ecologic) • Actualized by gene3c and developmental innova3ons leading to a new clade -
How are new evolutionary spaces created? • Poten+ated by broader
environmental segng (physical, gene3c, ecologic) • Actualized by gene3c and developmental innova3ons leading to a new clade • Refined by further developmental and ecological changes • Realized as innova3ons by ecological expansion and evolu3onary success -
Modern Synthesis • Transmission Gene3cs • Simple
path from genotype to phenotype • Primacy of gene3c inheritance • Selec3on within popula3ons as primary driver of evolu3on • Opportunis3c • Uniformitarian -
Emerging Perspec3ves • No simple mapping from genotype to
phenotype (evo-‐devo) • Mul3ple forms of inheritance • Mul3ple levels of selec3on • Important roles for muta3on and driU in addi3on to selec3on • Macroevolu3onary lags • Non-‐uniformitarian -
Questions • What factors drive innova3on, whether in biological,
cultural or technological systems? – Similar processes of varia3on, inheritance and selec3on and driU occur in all systems – Understanding processes in one may shed light on the others – Goal is to build models of innova3on that span different systems -
Degree of Excludability Rivalrous Non-rivalrous high low iPod GPS signal
Fish calculus Tragedy of the Commons -
Degree of Excludability Rivalrous Non-rivalrous high low iPod GPS signal
Fish Calculus Public Goods -
Degree of Excludability Rivalrous Non-Rivalrous high low Oxygen intertidal space
bioturbation Adaptations between clades Adaptations within a clade -
Degree of Excludability Rivalrous Non-Rivalrous high low intertidal space Adaptations
between clades Adaptations within a clade Oxygen Positive Feedback Spillover Effects