1 00:00:05,990 --> 00:00:05,430 we know a lot about the biological tree 2 00:00:07,510 --> 00:00:06,000 of life 3 00:00:09,350 --> 00:00:07,520 and can trace life's evolutionary 4 00:00:11,910 --> 00:00:09,360 history all the way back to a last 5 00:00:13,350 --> 00:00:11,920 universal common ancestor 6 00:00:14,870 --> 00:00:13,360 but for all that we understand about the 7 00:00:16,630 --> 00:00:14,880 tree of life there's still a great deal 8 00:00:18,550 --> 00:00:16,640 that we don't understand about its root 9 00:00:20,390 --> 00:00:18,560 system 10 00:00:22,550 --> 00:00:20,400 research on the origin of life can focus 11 00:00:24,790 --> 00:00:22,560 on any of a number of stages in life's 12 00:00:26,790 --> 00:00:24,800 emergence 13 00:00:28,070 --> 00:00:26,800 some origins of life research takes a 14 00:00:30,150 --> 00:00:28,080 top-down approach 15 00:00:32,310 --> 00:00:30,160 looking at the proximate ancestors to 16 00:00:34,229 --> 00:00:32,320 the last universal common ancestor 17 00:00:35,750 --> 00:00:34,239 with all of the historical contingencies 18 00:00:38,630 --> 00:00:35,760 they may have picked up along the way in 19 00:00:42,310 --> 00:00:40,389 alternatively one can take more of a 20 00:00:44,549 --> 00:00:42,320 bottom-up approach investigating the 21 00:00:46,229 --> 00:00:44,559 earliest stages of life's emergence 22 00:00:47,590 --> 00:00:46,239 when it only has the first intimations 23 00:00:50,069 --> 00:00:47,600 of lifelike behavior 24 00:00:53,830 --> 00:00:50,079 and when few significant historical 25 00:00:57,830 --> 00:00:55,590 auto catalytic cycles may have been an 26 00:00:59,990 --> 00:00:57,840 important part of life's chemical roots 27 00:01:00,790 --> 00:01:00,000 providing a means by which chemicals can 28 00:01:03,430 --> 00:01:00,800 collectively 29 00:01:05,189 --> 00:01:03,440 self-propagate the chemicals involved in 30 00:01:07,510 --> 00:01:05,199 auto-catalytic cycles 31 00:01:10,230 --> 00:01:07,520 can be split into three categories food 32 00:01:11,830 --> 00:01:10,240 species which only show up as reactants 33 00:01:13,750 --> 00:01:11,840 waste species that only show up as 34 00:01:15,990 --> 00:01:13,760 products and member species which show 35 00:01:17,749 --> 00:01:16,000 up as both products and reactants 36 00:01:20,390 --> 00:01:17,759 and whose abundance grow with each turn 37 00:01:21,990 --> 00:01:20,400 of the cycle 38 00:01:23,910 --> 00:01:22,000 here we have a simple toy model for an 39 00:01:25,429 --> 00:01:23,920 auto catalytic cycle consisting of two 40 00:01:26,710 --> 00:01:25,439 reversible reactions 41 00:01:28,469 --> 00:01:26,720 the first of which produces an 42 00:01:30,069 --> 00:01:28,479 intermediary member species and the 43 00:01:31,830 --> 00:01:30,079 second of which produces two of the 44 00:01:33,830 --> 00:01:31,840 original member species 45 00:01:36,469 --> 00:01:33,840 this provides a stoichiometric asymmetry 46 00:01:38,390 --> 00:01:36,479 that allows the cycle to grow and spread 47 00:01:40,149 --> 00:01:38,400 we simulate auto catalytic cycles in 48 00:01:41,670 --> 00:01:40,159 flow reactor environments where food 49 00:01:43,030 --> 00:01:41,680 flows in from a source to drive the 50 00:01:44,710 --> 00:01:43,040 system out of equilibrium 51 00:01:46,870 --> 00:01:44,720 and where all chemicals flow out of the 52 00:01:48,630 --> 00:01:46,880 reactor such that if a cycle doesn't 53 00:01:49,350 --> 00:01:48,640 propagate itself fast enough it will go 54 00:01:51,350 --> 00:01:49,360 extinct 55 00:01:52,789 --> 00:01:51,360 these simulations can be performed using 56 00:01:54,870 --> 00:01:52,799 mass action kinetics in which case 57 00:01:56,709 --> 00:01:54,880 chemical concentrations are continuous 58 00:01:58,389 --> 00:01:56,719 and the simulations are deterministic 59 00:02:00,389 --> 00:01:58,399 we're using the gillespie algorithm in 60 00:02:02,550 --> 00:02:00,399 which case chemical counts are discrete 61 00:02:04,149 --> 00:02:02,560 and the simulations are stochastic we 62 00:02:04,870 --> 00:02:04,159 use the gillespie algorithm in this 63 00:02:06,469 --> 00:02:04,880 presentation 64 00:02:08,229 --> 00:02:06,479 an example is on the right you can see 65 00:02:11,110 --> 00:02:08,239 the logistic growth of member species 66 00:02:12,949 --> 00:02:11,120 and waste species as food is depleted 67 00:02:14,309 --> 00:02:12,959 in 2020 we published a paper 68 00:02:15,750 --> 00:02:14,319 investigating the different types of 69 00:02:17,670 --> 00:02:15,760 ecological interactions that auto 70 00:02:19,589 --> 00:02:17,680 catalytic cycles might exhibit 71 00:02:22,710 --> 00:02:19,599 extending the analogy of auto catalytic 72 00:02:24,710 --> 00:02:22,720 cycles as species in an ecosystem 73 00:02:26,390 --> 00:02:24,720 we showed that auto catalytic cycles can 74 00:02:27,910 --> 00:02:26,400 compete for food sources 75 00:02:29,990 --> 00:02:27,920 exhibit facultative and obligate 76 00:02:32,630 --> 00:02:30,000 mutualisms with the waste of one 77 00:02:34,550 --> 00:02:32,640 serving as the food for another that the 78 00:02:36,150 --> 00:02:34,560 one cycle can prey on the member species 79 00:02:38,070 --> 00:02:36,160 of another cycle and that cycles can 80 00:02:40,710 --> 00:02:38,080 mutually inhibit one another 81 00:02:42,630 --> 00:02:40,720 the idea is that different ecological 82 00:02:44,390 --> 00:02:42,640 interactions can be composed to form 83 00:02:45,509 --> 00:02:44,400 stable ecosystems of increasing 84 00:02:47,110 --> 00:02:45,519 complexity 85 00:02:49,750 --> 00:02:47,120 to provide the scaffolding for later 86 00:02:51,830 --> 00:02:49,760 stages in the emergence of 87 00:02:53,830 --> 00:02:51,840 this previous work limited its analysis 88 00:02:54,790 --> 00:02:53,840 to auto catalytic cycles in well-mixed 89 00:02:56,390 --> 00:02:54,800 environments 90 00:02:58,470 --> 00:02:56,400 but the ecological possibilities for 91 00:03:00,470 --> 00:02:58,480 chemical ecosystems might be expanded if 92 00:03:02,390 --> 00:03:00,480 we consider different types of spatially 93 00:03:04,550 --> 00:03:02,400 structured environments instead 94 00:03:06,390 --> 00:03:04,560 for example reaction diffusion systems 95 00:03:08,630 --> 00:03:06,400 where cycles can spread 96 00:03:10,149 --> 00:03:08,640 to occupy new locations and thereby gain 97 00:03:11,990 --> 00:03:10,159 access to new food 98 00:03:14,470 --> 00:03:12,000 these will be the primary focus of this 99 00:03:15,910 --> 00:03:14,480 presentation 100 00:03:17,110 --> 00:03:15,920 there are several reasons the spatial 101 00:03:19,350 --> 00:03:17,120 structure might be important to the 102 00:03:20,869 --> 00:03:19,360 dynamics of chemical ecosystems 103 00:03:22,550 --> 00:03:20,879 first it might help to sustain more 104 00:03:24,229 --> 00:03:22,560 complex chemical ecosystems by 105 00:03:25,910 --> 00:03:24,239 permitting the coexistence of cycles 106 00:03:26,949 --> 00:03:25,920 that couldn't coexist in a well-mixed 107 00:03:30,630 --> 00:03:26,959 environment 108 00:03:32,070 --> 00:03:30,640 might select for spatial properties of 109 00:03:34,630 --> 00:03:32,080 auto catalytic cycles 110 00:03:36,630 --> 00:03:34,640 such as the permeability or diffusivity 111 00:03:39,030 --> 00:03:36,640 of their constituent chemicals 112 00:03:40,390 --> 00:03:39,040 and third spatial structure might create 113 00:03:42,309 --> 00:03:40,400 new levels of selection 114 00:03:43,430 --> 00:03:42,319 either favoring traits that couldn't be 115 00:03:45,910 --> 00:03:43,440 favored in the well-mixed 116 00:03:47,589 --> 00:03:45,920 environment analogous to group structure 117 00:03:48,949 --> 00:03:47,599 favoring different traits and biological 118 00:03:51,030 --> 00:03:48,959 populations 119 00:03:52,630 --> 00:03:51,040 or creating new units of selection 120 00:03:54,149 --> 00:03:52,640 altogether 121 00:03:56,149 --> 00:03:54,159 first i'm going to present a simple 122 00:03:57,589 --> 00:03:56,159 example where a spatially structured 123 00:03:59,589 --> 00:03:57,599 environment permits a more complex 124 00:04:01,030 --> 00:03:59,599 chemical ecosystem to be maintained 125 00:04:03,110 --> 00:04:01,040 then could otherwise be maintained in 126 00:04:05,190 --> 00:04:03,120 the well-mixed case this is going to be 127 00:04:07,429 --> 00:04:05,200 similar in spirit to the bz reaction 128 00:04:09,509 --> 00:04:07,439 which has auto catalytic mechanisms 129 00:04:11,110 --> 00:04:09,519 and which while oscillating between two 130 00:04:13,429 --> 00:04:11,120 states in the wellmix case 131 00:04:15,990 --> 00:04:13,439 exhibits stable and dynamic patterns and 132 00:04:17,909 --> 00:04:16,000 as a reaction diffusion system 133 00:04:19,749 --> 00:04:17,919 this example is going to consist of two 134 00:04:20,310 --> 00:04:19,759 mutually inhibiting auto catalytic 135 00:04:22,629 --> 00:04:20,320 cycles 136 00:04:23,830 --> 00:04:22,639 a and b which are colored red and blue 137 00:04:25,270 --> 00:04:23,840 respectively 138 00:04:26,629 --> 00:04:25,280 each cycle is supplied with an 139 00:04:29,189 --> 00:04:26,639 independent food source so that they're 140 00:04:30,870 --> 00:04:29,199 not directly competing for food 141 00:04:32,950 --> 00:04:30,880 each consists of two reversible 142 00:04:34,390 --> 00:04:32,960 reactions identical to the toy model i 143 00:04:36,629 --> 00:04:34,400 initially showed 144 00:04:37,990 --> 00:04:36,639 additionally we include two reversible 145 00:04:40,230 --> 00:04:38,000 inhibition reactions 146 00:04:42,469 --> 00:04:40,240 which react the waste of one cycle with 147 00:04:43,510 --> 00:04:42,479 the food of the other cycle to produce 148 00:04:46,150 --> 00:04:43,520 another species 149 00:04:47,270 --> 00:04:46,160 x or y that neither cycle can directly 150 00:04:49,270 --> 00:04:47,280 use 151 00:04:51,510 --> 00:04:49,280 the effect of this is that if one cycle 152 00:04:54,070 --> 00:04:51,520 increases its abundance more quickly 153 00:04:55,430 --> 00:04:54,080 the waste that it produces can inhibit 154 00:04:57,670 --> 00:04:55,440 the growth of the other cycle 155 00:04:59,990 --> 00:04:57,680 ultimately driving it extinct and once 156 00:05:00,710 --> 00:05:00,000 again all chemicals will be constantly 157 00:05:03,189 --> 00:05:00,720 diluted 158 00:05:06,469 --> 00:05:03,199 creating a selective pressure for cycles 159 00:05:08,390 --> 00:05:06,479 that can propagate more quickly 160 00:05:09,670 --> 00:05:08,400 instead of simulating this chemical 161 00:05:11,830 --> 00:05:09,680 reaction network 162 00:05:13,909 --> 00:05:11,840 in a singular flow reactor will simulate 163 00:05:16,150 --> 00:05:13,919 it in a reaction diffusion system 164 00:05:18,230 --> 00:05:16,160 where each pixel has inflow from a 165 00:05:20,870 --> 00:05:18,240 source and outflow into a sink 166 00:05:24,870 --> 00:05:20,880 but also exchanges its chemical contents 167 00:05:27,110 --> 00:05:24,880 with neighboring pixels via diffusion 168 00:05:29,270 --> 00:05:27,120 more specifically we'll use a 5x5 169 00:05:31,029 --> 00:05:29,280 reaction diffusion system with periodic 170 00:05:33,510 --> 00:05:31,039 boundaries 171 00:05:34,390 --> 00:05:33,520 now if we were to seed every pixel in 172 00:05:37,590 --> 00:05:34,400 this system 173 00:05:38,550 --> 00:05:37,600 uniformly with equal amounts of cycles a 174 00:05:41,350 --> 00:05:38,560 and b 175 00:05:43,189 --> 00:05:41,360 but with no diffusion it would be 176 00:05:46,310 --> 00:05:43,199 possible to have an outcome like this 177 00:05:49,510 --> 00:05:46,320 in which cycles a and b dominate 178 00:05:51,270 --> 00:05:49,520 in adjacent pixels and stably coexist 179 00:05:53,749 --> 00:05:51,280 because there is no interaction between 180 00:05:54,310 --> 00:05:53,759 those pixels if we were to add diffusion 181 00:05:57,909 --> 00:05:54,320 in 182 00:05:59,990 --> 00:05:57,919 this sort of outcome would be unstable 183 00:06:01,510 --> 00:06:00,000 for example with any slight imbalance 184 00:06:03,270 --> 00:06:01,520 like blue coming to dominate in the 185 00:06:05,830 --> 00:06:03,280 center 186 00:06:07,749 --> 00:06:05,840 accumulated member species by cycle b in 187 00:06:09,909 --> 00:06:07,759 the center could diffuse outwards 188 00:06:13,510 --> 00:06:09,919 and strengthen the invasion of pixels 189 00:06:17,430 --> 00:06:15,430 and with high enough diffusion rates we 190 00:06:19,590 --> 00:06:17,440 would expect the whole system to reach 191 00:06:21,990 --> 00:06:19,600 one global outcome 192 00:06:23,510 --> 00:06:22,000 here we have stochastic simulations of 193 00:06:25,670 --> 00:06:23,520 the reaction diffusion system 194 00:06:26,550 --> 00:06:25,680 under three different conditions where 195 00:06:29,189 --> 00:06:26,560 we're varying 196 00:06:31,029 --> 00:06:29,199 the rate constant for the diffusion of 197 00:06:32,790 --> 00:06:31,039 all chemicals in the system 198 00:06:35,909 --> 00:06:32,800 we have a slow diffusion case a moderate 199 00:06:37,909 --> 00:06:35,919 diffusion case and a fast diffusion case 200 00:06:39,749 --> 00:06:37,919 here we have time series plots for the 201 00:06:40,790 --> 00:06:39,759 total number of member species belonging 202 00:06:42,710 --> 00:06:40,800 to each cycle 203 00:06:45,430 --> 00:06:42,720 and each pixel of the reaction diffusion 204 00:06:47,430 --> 00:06:45,440 system for each of the three cases 205 00:06:48,870 --> 00:06:47,440 on the left in the slow diffusion case 206 00:06:51,670 --> 00:06:48,880 we can see that each pixel 207 00:06:53,670 --> 00:06:51,680 quickly has one cycle dominate and that 208 00:06:55,110 --> 00:06:53,680 a low amount of material is exchanged 209 00:06:57,430 --> 00:06:55,120 between reactors 210 00:06:59,670 --> 00:06:57,440 such that each cycle struggles to invade 211 00:07:02,070 --> 00:06:59,680 adjacent pixels 212 00:07:03,830 --> 00:07:02,080 on the right we see the opposite extreme 213 00:07:05,990 --> 00:07:03,840 a large amount of chemicals are 214 00:07:07,909 --> 00:07:06,000 exchanged between adjacent pixels 215 00:07:10,070 --> 00:07:07,919 so that the plots tend to resemble one 216 00:07:10,550 --> 00:07:10,080 another and a global outcome is quickly 217 00:07:13,510 --> 00:07:10,560 reached 218 00:07:15,830 --> 00:07:13,520 approximating a well-mixed reactor in 219 00:07:17,830 --> 00:07:15,840 the moderate diffusion regime each pixel 220 00:07:18,469 --> 00:07:17,840 alternates between being dominated by 221 00:07:21,670 --> 00:07:18,479 cycle a 222 00:07:23,990 --> 00:07:21,680 and cycle b neither cycle wins globally 223 00:07:25,589 --> 00:07:24,000 and each shifts around its advantage 224 00:07:27,430 --> 00:07:25,599 forming patterns reminiscent 225 00:07:30,309 --> 00:07:27,440 of the spatial patterns of the bc 226 00:07:35,189 --> 00:07:30,319 reaction in a petri dish 227 00:07:39,670 --> 00:07:37,510 next i'll continue using the example of 228 00:07:40,790 --> 00:07:39,680 mutually inhibiting cycles in a reaction 229 00:07:42,550 --> 00:07:40,800 diffusion system 230 00:07:44,309 --> 00:07:42,560 to show a case where the spatial 231 00:07:46,550 --> 00:07:44,319 properties of auto catalytic cycles can 232 00:07:48,390 --> 00:07:46,560 be selected for 233 00:07:50,950 --> 00:07:48,400 we'll take the same two mutually 234 00:07:52,950 --> 00:07:50,960 inhibiting cycles that we had before 235 00:07:55,029 --> 00:07:52,960 but instead of making them identical to 236 00:07:57,510 --> 00:07:55,039 one another in their rate constants 237 00:07:58,950 --> 00:07:57,520 and the diffusion constants associated 238 00:08:01,270 --> 00:07:58,960 with their chemicals 239 00:08:02,150 --> 00:08:01,280 we're going to make them differ in two 240 00:08:04,550 --> 00:08:02,160 ways 241 00:08:06,070 --> 00:08:04,560 the red cycle is going to be fiercer in 242 00:08:08,390 --> 00:08:06,080 the sense that it's going to have 243 00:08:10,469 --> 00:08:08,400 reactions with higher rate constants 244 00:08:11,990 --> 00:08:10,479 but the blue cycle is going to be faster 245 00:08:16,550 --> 00:08:12,000 meaning that its member species are 246 00:08:20,710 --> 00:08:18,629 we are going to do this in a 3x3 247 00:08:21,670 --> 00:08:20,720 reaction diffusion system with periodic 248 00:08:24,150 --> 00:08:21,680 boundaries 249 00:08:25,110 --> 00:08:24,160 where both cycles are only seated in the 250 00:08:29,110 --> 00:08:25,120 center pixel 251 00:08:34,790 --> 00:08:32,230 the expectation is that cycle a in red 252 00:08:36,230 --> 00:08:34,800 being fiercer will tend to dominate in 253 00:08:39,110 --> 00:08:36,240 the central pixel 254 00:08:39,990 --> 00:08:39,120 whereas cycle b in blue being faster 255 00:08:42,230 --> 00:08:40,000 will tend to spread 256 00:08:45,750 --> 00:08:42,240 more quickly to adjacent pixels and 257 00:08:48,710 --> 00:08:45,760 thereby access new food more quickly 258 00:08:49,750 --> 00:08:48,720 as cycle b continues to expand it might 259 00:08:51,110 --> 00:08:49,760 be able to build up 260 00:08:53,190 --> 00:08:51,120 enough of an advantage in the 261 00:08:54,150 --> 00:08:53,200 surrounding pixels to re-invade the 262 00:08:57,829 --> 00:08:54,160 central pixel 263 00:09:00,070 --> 00:08:57,839 and overcome cycle a here we have an 264 00:09:02,070 --> 00:09:00,080 animation of the unfolding of time 265 00:09:04,070 --> 00:09:02,080 series of the total number of member 266 00:09:07,190 --> 00:09:04,080 species for each cycle in each pixel of 267 00:09:10,470 --> 00:09:09,590 in the central pixel cycle a being 268 00:09:11,990 --> 00:09:10,480 fiercer 269 00:09:14,710 --> 00:09:12,000 drives cycle b to the brink of 270 00:09:17,030 --> 00:09:14,720 extinction but cycle b being faster 271 00:09:18,630 --> 00:09:17,040 is able to diffuse into adjacent sites 272 00:09:20,150 --> 00:09:18,640 and build up an advantage in those 273 00:09:22,230 --> 00:09:20,160 pixels more quickly 274 00:09:23,750 --> 00:09:22,240 so that it can suppress the growth of 275 00:09:26,230 --> 00:09:23,760 cycle a 276 00:09:27,829 --> 00:09:26,240 eventually cycle b is able to re-invade 277 00:09:29,590 --> 00:09:27,839 the central pixel 278 00:09:33,030 --> 00:09:29,600 to such an extent that it begins to 279 00:09:34,870 --> 00:09:33,040 drive cycle a towards extinction 280 00:09:36,870 --> 00:09:34,880 the outcome of this type of simulation 281 00:09:39,030 --> 00:09:36,880 largely depends on the relative fastness 282 00:09:40,870 --> 00:09:39,040 and fierceness of cycles a and b 283 00:09:43,110 --> 00:09:40,880 here we have a heat map in which we 284 00:09:45,829 --> 00:09:43,120 sweep over those parameters 285 00:09:48,470 --> 00:09:45,839 on the left we sweep over the diffusion 286 00:09:50,470 --> 00:09:48,480 constants for the chemicals of cycle b 287 00:09:52,230 --> 00:09:50,480 where as we go down cycle b gets 288 00:09:54,630 --> 00:09:52,240 increasingly fast 289 00:09:55,750 --> 00:09:54,640 on the bottom we sweep over the reaction 290 00:09:58,550 --> 00:09:55,760 rate constants 291 00:09:59,750 --> 00:09:58,560 for cycle b's reactions whereas we move 292 00:10:03,829 --> 00:09:59,760 from right to left 293 00:10:05,670 --> 00:10:03,839 cycle b gets increasingly less fierce 294 00:10:06,870 --> 00:10:05,680 the colors in the heat map encode the 295 00:10:09,430 --> 00:10:06,880 final frequency 296 00:10:10,230 --> 00:10:09,440 of member species for cycles a and b 297 00:10:13,430 --> 00:10:10,240 aggregated 298 00:10:15,509 --> 00:10:13,440 over the reaction diffusion system we 299 00:10:17,750 --> 00:10:15,519 find parameter combinations where 300 00:10:20,310 --> 00:10:17,760 fastness overcomes fierceness and where 301 00:10:22,069 --> 00:10:20,320 fierceness overcomes fastness 302 00:10:24,069 --> 00:10:22,079 meaning that either could be selected 303 00:10:26,150 --> 00:10:24,079 for 304 00:10:28,310 --> 00:10:26,160 additionally while it is always better 305 00:10:29,750 --> 00:10:28,320 to be fiercer it is not always better to 306 00:10:32,230 --> 00:10:29,760 be faster 307 00:10:33,190 --> 00:10:32,240 in the bottom left we see a region where 308 00:10:35,750 --> 00:10:33,200 cycle b 309 00:10:37,590 --> 00:10:35,760 being faster gives it a disadvantage to 310 00:10:40,310 --> 00:10:37,600 cycle a 311 00:10:41,910 --> 00:10:40,320 likely because its members diffuse so 312 00:10:43,829 --> 00:10:41,920 quickly that they can't stably 313 00:10:45,750 --> 00:10:43,839 accumulate 314 00:10:47,190 --> 00:10:45,760 in addition to simple reaction diffusion 315 00:10:48,870 --> 00:10:47,200 systems there are various other 316 00:10:50,550 --> 00:10:48,880 spatially structured environments that 317 00:10:52,310 --> 00:10:50,560 may be relevant to the origin of life 318 00:10:53,910 --> 00:10:52,320 and to the dynamics of auto catalytic 319 00:10:56,069 --> 00:10:53,920 chemical ecosystems 320 00:10:58,230 --> 00:10:56,079 for example mineral surfaces where 321 00:10:59,030 --> 00:10:58,240 chemicals can adsorb and desorb from a 322 00:11:03,430 --> 00:10:59,040 surface 323 00:11:05,269 --> 00:11:03,440 and also provide a new basis for 324 00:11:07,269 --> 00:11:05,279 competition between auto catalytic 325 00:11:08,710 --> 00:11:07,279 cycles as they compete for adsorption 326 00:11:10,710 --> 00:11:08,720 sites 327 00:11:12,310 --> 00:11:10,720 compartments are another important class 328 00:11:12,949 --> 00:11:12,320 of spatial structures that might affect 329 00:11:15,030 --> 00:11:12,959 the dynamic 330 00:11:16,870 --> 00:11:15,040 chemical ecosystems they might be 331 00:11:19,829 --> 00:11:16,880 semi-permeable or closed 332 00:11:21,430 --> 00:11:19,839 they might grow and or divide some 333 00:11:22,150 --> 00:11:21,440 examples of these in the origins of life 334 00:11:25,430 --> 00:11:22,160 literature 335 00:11:26,470 --> 00:11:25,440 are vesicles and coagulate some forms of 336 00:11:28,630 --> 00:11:26,480 spatial structure 337 00:11:30,710 --> 00:11:28,640 especially compartments provide the 338 00:11:32,550 --> 00:11:30,720 possibility of new levels of selection 339 00:11:34,310 --> 00:11:32,560 especially when the dynamics of the 340 00:11:36,230 --> 00:11:34,320 spatial structure become coupled to the 341 00:11:38,630 --> 00:11:36,240 chemistry itself 342 00:11:40,389 --> 00:11:38,640 i'd like to gratefully acknowledge my pi 343 00:11:41,670 --> 00:11:40,399 david baum who i've been working with 344 00:11:43,190 --> 00:11:41,680 through the hildale undergraduate 345 00:11:44,870 --> 00:11:43,200 faculty research fellowship at the 346 00:11:46,630 --> 00:11:44,880 wisconsin institute for discovery 347 00:11:48,069 --> 00:11:46,640 and chris kemp is my mentor at the santa 348 00:11:50,230 --> 00:11:48,079 fe institute for the undergraduate 349 00:11:51,590 --> 00:11:50,240 complexity research program 350 00:11:53,030 --> 00:11:51,600 also the graduate students and 351 00:11:54,550 --> 00:11:53,040 post-doctoral students that i've been 352 00:11:55,750 --> 00:11:54,560 working with at the wisconsin institute 353 00:11:57,430 --> 00:11:55,760 for discovery 354 00:11:59,509 --> 00:11:57,440 and the other undergraduates in the bomb 355 00:12:01,030 --> 00:11:59,519 lab as well 356 00:12:02,790 --> 00:12:01,040 for additional reading you can check out 357 00:12:04,470 --> 00:12:02,800 our paper from last year in ecological 358 00:12:07,430 --> 00:12:04,480 framework for the analysis of prebiotic 359 00:12:08,790 --> 00:12:07,440 chemical reaction networks