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Good morning everybody let's get started so we started yeah so you can still hear me right yeah okay yesterday we started talking about how plants avoid selfing and we didn't quite finish it so we are still in the subject and here I just kind of want to integrate what we've seen yesterday where you know when if you have to just want flour per plant spatial separation temporal separation works but once you have more than one you run into trouble and so here is an example so this is Sage where we have here in fluorescence where flowers at the bottom open before the flowers at the top per flower it goes through male it goes through the two Sexes separately so in this individual we have these flowers are in the male face these flowers are in the female face so if an insect lands here at the bottom it picks up pollen then what's up up to the upper flowers it will deposit its own pollen and hence with a special with temporal separation with more than one flower in an inflorescence with where they are not perfectly coordinated accidents still happen and then easy to understand that even though this species a is putting distance between the answers accidents can still happen which is using the flip side the stigma lower down below the answers accidents can still happen so so this is not a completely foolproof way how to eliminate selfie and so really the ultimate way how to not get self is through self incompatibility so let me tell you how how this works so self incompat some portions of the female reproductive organ recognize the biochemical composition of the pollen grain and the pollen tube and they realize oops this is genetically my own pollen I don't want to be self and so I am going to shut down to growth of this pollen grain so it is a biochemical recognition which leads to no fertilization with I need a very simplified Outlook this is what what is happening so I am color coding the flower here red as the red genetic background on its stigma we have two pollen grains which have landed one is also red so it's self pollen the other one is a different genetic individual outcross pollen and so the FEMA reproductive organ essentially can stop the growth of this pollen grain at three times it can stop it at the stigmatic level where it's kind of plugging up the stigmatic surface it can stop it in the style it can also stop it further down as the pollen tube is reaching the ovule so three times three locations where the FEMA reproductive organ recognizes this is my own pollen I want to stop it the biochemistry and the genetics of self-income incredibly complex so this is just a placeholder showing you that here that yeah it's highly highly complex I could spend 5 hours just talking about self-income which I want to so let me just tell you it's complex okay so self incompatibility is very common in angiosperms and it's also common in some of the plans which feed the world so for example apples are self incompatible apple has hermaphroditic flowers with both male and female functions but if you have one single apple tree in your garden you will not Harvest any Apples because even if South pollen lands on the stigma it will not lead to pollination and hands are fertilization that the production of apples so if you want to harvest apples you need at least two genetically distinct individuals in order to harvest apples and the very same self incompatibility is present in many other species apples belong to the Rose family all of these also belong to the Rose family so pears cherries plums all of these species are self incompatible a different genetic individuals in your orchard to harvest okay so now I kind of want to step back and integrate across the street topics to show you that plants often don't just use one mechanism but they they cherry pick between them and often self incompat is used in connection with either temporal or spatial separation and one particular example which I'll show you actually uses all three before we go there so let's look at what the main target function is so we've seen that temporal and spatial separations so the mechanics of essentially getting a pollen grain on to an insect on a very specific part of its body and then picking up a pollen grain from the specific portion of the body so that pollination is effective and I'll I'll show you this in the next few slides about for now I just kind of want to say that the current modern interpretation of temporal and spatial separations is yes it helps with self avoidance a little bit but the big role is to not waste any self incompatibility number one ticket item how to avoid selling okay so I'm going to show you now how self how special separation temporal separation is used to really increase the effectiveness of pollen pickup and deposition it is present in this Sage species which I already mentioned at the beginning of today's lecture sage has a really really cool mechanism how the flower a Pen's pollen onto the body of a insect so here is a cross-section to the flower answer which is inserted here or grows from from a point in the wall but it is likewise connected to a branch lower down which is a lever mechanism so this is an entire Branch making up the answer inserted here if the insects lands on the flower and it wants to feed on the nectar which is hidden here it can only get to the nectar if it's head pushes this lever which then brings down the answer and paste the pollen on the bum of the insect and that's exactly what you can see here so the insect here is feeding on the nectar it's head pushes the lever the the answer now comes down and deposits the the pollen on a specific portion of the Beast bum while the flower here is in the male face so the flower starts out male the answer is actively shedding shedding pollen while the stigma here is kind of out of the way and also not receptive so that's what you can see here the insect is actually feeding the answers are coming out and are sticking to pollen grains on the back of the insect so now we go from male face to female face the stigma now is elongating growing to be in a position where previously the insect have has received its pollen grades so once the stigma is done growing you can see now it's it's really in a different position compared to the start which is exactly where the the next insect which hopefully has visited a male flower first now the stigma is picking up the pollen so essentially the plant isn't wasting pollen grains to apply them to the entire insect surface it really doesn't exactly in one location where in the next phase that female can pick the pollen up so we have essentially both temporal and spatial separation we go through male face first then female and while the flowers in the male face we get a nice facial distance between the stigma and and the the answers and yes because now you get the two sexual phases overlapping within an individual let me see what I was yes so you can get the opportunity for selfie so again if the bee picks up first and then goes to a female flower that is an issue and this is why Sage besides having this really intricate mechanical adaptation to pollen release and pick up it is also throwing in South incompatibility so if these accidents happen there is still no selfie so so this really shows you that this these mechanical adaptations are less so for avoiding of selfing but for the really very targeted application and pick up of pollen grade so essentially temporal and spatial separations for an increase of ease of Poland pickup and delivery better mechanics less pollen waste while self-income ultimate Way of avoiding something and here is a video which actually shows you this mechanism in action so it is voice over German we don't need that so you can see the beat has landed it's the the pollen is being applied same again the answers come out and apply it to the beat you can see how the lever mechanism works wonderfully to apply here is the experimenter actually shows you the activity of the head of the B how the lever comes out and applies the pollen okay so I would argue pretty cool okay so now we've seen how Sage is using bees for a very very effective position so let's not look how flowers have come have been have adapted to to be to use living and non-living as I already said it are a genius solution of angiosperms essentially to pick up pollen grains and deposit them in a non-directed i'll explain what I mean if that's in a bit and so the evolutionary invention of flowers really led to the extreme diversity of types of flowers and also to the fact that it's the age of sperms which rules the world so largest diversity of flowers of triggered the largest diversity on planet Earth ever and it's all about how to manipulate this pollen vector okay so who are the factors we have an abiotic Vector which is wind and then we have a number of biotic vectors so I'm going to to walk you through these but in all of these cases essentially the flower over evolutionary time to Natural Selection needs to adjust its floral architecture to optimize Poland i'm also really adapt to what how the pollinator sees the world in order to attract it so in terms of sight smells taste and touch and then pollinators don't just come for the love of flowers they have their own agenda and so the flowers need to pay back and so they need to get to adapt to the food requirements of the pollinators to produce you know putting these three points into natural selection this then results in this huge enormous range of flowers shape color older and nature of reward okay so I told you that there's a non-directed and because when can't be trained come here and now go to the next Plant this is non-directed address of biotic pollination by animals is more directed because animals learn to read the world and can go to targeted plants I should also say that there is a very very small handful of plans which is pollinated by water I'm not going to talk about it wind is very very important okay so I want to start with wind pollination if we look at all plans that then 10% of their of them are with pollinated the occurrence of wind pollination is not random across habitats so up high and up north or away from the equator it's more common whenever you don't have Forest which is covering the landscape you get a better kind of attack by wind so up high on Mountains close to the poles there is more there's few trees to more wind likewise dry environments think deserts also don't support tree growth so wind is a good bet there so it integrating across these really it is open vegetation which has more wind pollination than else and then lastly Island Florida tend to have higher proportion of wind pollinated plants because you know think about it if a plant gets to the island and it's pollinator isn't here it is toast so if the plans which arrives to an island will always be there fewer insects or fewer trees and more wind are those which are generally which generally have more wind pollination flowers of wink pollinated plants aren't pretty there is no colors no showiness no red pedals Etc so here are several examples of grasses all grasses are wind pollinated here we see answers the wind can shake them and release the pollen grains here we have the highly highly branched stigma which are trying to filter out the pollen grains from the air same thing same thing here dangling answers on really really fine thread like filaments so that the wind can shake them and then here we have stigmas stigmas filtering out the pollen here's a few more examples so these were grasses the and now here we're looking at trees so that the windows very common in Ontario wind pollinated it's it's male flowers are all super super long branches where the whole thing again shakes really easy so generally speaking let's summarize on wind pollination the flowers are small and inconspicuous the plants can save carbon building blocks don't have to invest anything into advertisement or reward so no callers no nectar but we've seen long filaments and very typically these long and feathery and branched Styles and stigmas to to filter out of the air because the wind can't be trained typically only a very very small fraction of release pollen grains actually reaches the stigma so it's regarded as wind pollination is regarded as cheap but not very efficient and a very large quantity of pollen is necessary here is a look at a forest which is in peak flower of a Winter's plans and you can see the massive amounts which need to be produced where again a small proportion of this pollen will make it onto the female flower okay so I want to switch to biotic pollination where we're focusing on five animals which do the job they can be trained so it is more precise and directed but the plans need to invest into reward so a special reward pollen nectar and the flowers need to be constructed in a way that they fit the physical requirements sizes shapes off of the of the a small subsection of pollinators convince the pollinators that they're getting a great deal best possible nectar grade construction of flower good advertisement so that these animals don't go to a different species but learn to use this very one species and just go from one McDonald's to the next of this one species so the more restricted you are the more of chance you get to you have to get your own pollen grates this this level of restriction however is a Continuum between very low specialization so plans essentially which are generalists and pretty much take anybody who visits versus the other end of the spectrum plants which really really rely on a very small number of pollinators where sometimes there is a exclusive relationship where one species of pollinator loves this particular restaurant so well that's this restaurant lives off this one species of pollinator a one-on-one here's a picture of one species of golden Rock which also occurs in Ontario it's one of the same species and you can see it's visited and pollinated by a whole huge range of insects from butterflies moths large and small bees then we have flies and we have beetles so essentially Goldenrod is the classic generalist plant it constructs tiny flowers so this is actually one flower and then it puts many many flowers into a surface where any insect can essentially land giant or or smaller and can kind of feed on a average blendola food which everybody likes typically it's multiple flowers multiple small flowers making up a platform where again a whole range of insects can roam around and do its thing generally have to provide non-specialized average pollen and nectar generous plans have to deal with the fact that they often would get pollen grains from not just their own species because these insects might not be visiting just one type of flower okay so now let's look at the more specialized end of the spectrum where plants are using just a single group of pollinators starting with bees so please are the most important group of biotic pollinators bees pollinate more species worldwide than any other group these originated about 80 million years ago this is when the lots and lots of you know the where the diversification of the bee species started and interesting that this was also the time these 80 million years ago Where Angels really took off in speciating into lots and lots of species so there was definitely kind of a back and forth abby's love ain't your sperms Angels Burns they get you know they call evolved together so hands there is definitely kind of a back and forth increasing their species numbers adult bees live on nectar so all be pollinated plants need to produce nectaries and the sugar needs to be relatively concentrated 30 to 35% sugar bees however also need to feed their young and anybody who's growing needs protein and so the juveniles are fed on pollen pollen is rich in protein so be pollinated plants need to produce a surplus of pollen because some of this pollen will be eaten by the Bee larvae bees have a very specific site so they see us they they see a specially well in the blue and the yellow range so whenever you see blue flowers and yellow flowers very very likely therapy canola mustard plant as it appears to our own site but if you shine UV light on them which these could see you can see that the center of the flower is highlighted and that there are veins highlighting the the pathway to the nectar and to pause so be pollinated plants have blue yellow and UV colors these are all so smart these are among the smartest of insects they can be trained to handle plans faster so the more often they visit one particular species the better they can serve it and so the plans The evolutionary speaking have figured that out and they're using what are called nectar guys pointing towards the entrance to the to the flower where there where nectar and and pollen can be had so that essentially a bee as it is learning to use these flowers can visit more flowers per unit exporting and importing more pollen grains per time so all of these are these nectar guys with nice also you know color combos to really highlight the way to the goodies the nectar needs to be hidden it is commonly hidden in a way that they it can only be accessed by the correct type of pollinator hence the bee so nectar tends to be hidden at the very bottom of a flower in the case of this flower the entrance is actually closed and as bees are relatively heavy and strong they can pry open the entrance and then reach the nectar while other insects like slime which are long enough for the Beast to reach them with their proboscis but not for flies so we can summarize for bee pollination so bees the best in the range yellow blue and UV bees do not see red whenever you see a color a flower and it's red it's not to be it's not a bee pollinated flower these are smart and can learn how to read nectar guys and then the plant wants to hide it's good he's the reward that's only the Adaptive Beast can actually reach it in terms of architecture and also open mechanisms because again these are relatively strong there are however plans which love to be serviced by bees but which do not provide a classic reward so these are essentially cheating plans which you know make the bees work hard but there is a limited or no reward there's allows the plans to limit their cost of reproduction this cheating by plants really only works because in a given ecosystem to be there's always way more honest plans where these can get a reward than cheaters so as long as the cheating plants are weird bees will have only a limited opportunity the mail bees as they're cruising the landscape they pick up the smell they're thinking oh yeah I'm going to get to fertilize a a b so the males will land on these flowers they will try and copulate during their efforts to calculate they will pick up the pollen grains they sadly will leave without a reward but they will pick up the smell and The Lure of the next four kids will deposit the pollen grains and so and so this is an example where the bees don't get anything out of it but where the plant has to make crazy adaptations to really come up with the same scent surface hairs shade colors as female bees and so I have a really cool movie which shows you that but before I go there so here is one of such cheating Orchid so here is the body kind of the fake body of the female the male has landed and it's trying to calculate and it is picking up here in the case of orchids the pollen don't come individually and the warmer parts of Europe lives a whole group that Bamboozled their pollinators into thinking that they're going to get a really Sensational reward their little orchids flowers reproduce he can do about it and baby give me a second okay nope you let me know you pause because this time he deposits the pollen on another bogus female the hands on many of these all kids so yes so in this case obviously the plans isn't actually getting away with fewer resources it needs to invest quite a bit but it's it's are you sight and smell the smell is kind of nice and sweet nothing nasty about it in order to again separate butterfly pollinated plants from bee pollinated plants red and orange are the most commonly used colors of butterfly pollinated plants and again they have these really long long which allow them to reach very far down into the narrow tube which animals closer related to butterflies are are Hawk Moss Hawk Moss fly generally in the night so in the night plants can essentially save carbon building blocks on colors so hot pollinated flowers tend to be white or very pale however what they save in color the plants have to invest much more heavily into scent so hot smell so the flowers need to smell very very sweet similarly as butter fly Hawk moths have really long proboscis so that the floral tubes tend to be super long again to exclude everybody else and then the nectar is again inserted at the very bottom of each individual flower okay so let's integrate so yes moths are night active white or dull flowers with a very strong sense sense a smell so which is mostly admitted in the night so again the plan is kind of saving carbon build building blocks and is releasing the perfume only in the night and then it has to adjust to the architecture by having this long and narrow floral tube and also a little platform where the insect of the Hawks can land hummingbird pollinated plants also use the color of red in order to not overlap with the bee pollinated colors so red is the color which hummingbirds are most trained to in contrast to butterflies hummingbirds can hover so there there is no need for a landing platform is relatively long and even longer is it's elaborate tongue so the tongue when it's not feeding is obviously in this and actually further back in the in the head and then it can extended once it wants to feed to a really enormous length and the tongue of somebody hummingbirds is really really intricate it's actually split in multiple branches which are kind of feathery which make the tongue not work like a spoon but almost like a sponge for very liquid nectar so the sponge really only works if the electric isn't too concentrate it to stop up the liquid so hummingbird pollinated flowers need to produce a really big volume of relatively runny nectar and the hummingbirds then use this nectar obviously both for energy but also as a drinking station to distinguish hummingbird pollinated flowers from from butterflies again so we both have a long long Corolla to exclude other insects but indicates of hummingbirds are way wider than the proboscis of butterflies so that so the width of the floral tube has to be significantly wider than the one of butterflies okay so integrate through that birds have a good sense of color and are attracted to red a little less to Yellow they don't smell so hummingbirds don't smell so plants can save their energy there is no flower odor I told you that hummingbirds at least some of them have this weird split tongue so the nectar needs to be more liquid than in the case for insects and more of it and then we've seen the long tubular fuse corolla to suit the long beak which has to be wider than in the case of butterflies or moths and I don't know why I got through this really quickly but you're released and happy weekend