📷 Hana Thompson Journalist: Emily O’Halloran
Interviewer: Okay we're joined here today with Hana Thompson who recently completed her thesis on the implications of island colonization on the plant species abronia umbellata welcome Hana.
Hana: Thank you for having me.
Interviewer: So do you think you could just give us a quick overview of what your research was?
Hana: Yes like so you said I was studying the plant species of Iranian balada it's common name is pink sand ravena it's a Pacific coastal dune species so it grows on sand dunes out along the West coast of North America so it grows from mid Oregon down into Baja California but it's also present on some of the California Channel Islands which are found off the coast of Southern California so my research was interested in looking at how this island colonization has impacted this species um so I looked at mating system and population genetics.
Interviewer: Cool it's super cool so um does this research have any applications beyond the specific plant that you were studying?
Hana: Yeah so we we kind of wanted to get a better idea of how island colonization of affect species in general um islands are often the focus of a lot of conservation studies because there's often a lot of endemic species on islands so species that are only found on those islands and nowhere else and so they're often focus of a lot of conservation studies and there's also a theory that island species have lower genetic diversity which can make them more risk more prone to extinction so for that reason why lot of conservation efforts are focused on islands so we kind of wanted to take target species and see if these theories about diversity and being more risker are true.
Interviewer: Cool so just to clarify why islands are lacking diversity versus you know mainland?
Hana: Again there's a few different theories but one of the main ones is due to founder effect so if you think of so you think of genetic diversity so in your genome it's made up of jeans right differentiating second roll different things but different individuals of the same species can have different versions of that gene that do the same thing that can be slightly different due to mutations and having more mutations increases the population genetic diversity and it can make it easier for them to respond to changes in their environment 'cause they have sort of a bigger arsenal of ways that they can deal with different things in their environment so if you think of like a population on the mainland if you think of their genetic diversity is like a bowl of marbles of different colours so there's like 8 different colours so eight different versions of a gene if you take three marbles out and put them on an island you're going to have fewer colours right so those populations even if they grow and become the same size as the one in the mainland there going to have less colours.
Interviewer: Right so they're like isolated kinda thing?
Hana: Yeah exactly and Assuming that they are not able to mate with the ones on the mainland because they separated by a lot of water then there only ever going to have those two colours or whatever and there will be less able to deal with maybe disturbances in their environment.
Interviewer: Right interesting okay how is it colonized like what is it that is colonizing ends are you talking about human colonization?
Hana: It can be it depends on the species furbo neon balada so they put their seeds in these structures called anther carps so basically the way the flower looks has its own stamina there's ahead and there's a bunch of Flowers you just like 10 to 15 Flowers each flower will make anantha carp which is just a little structure and inside that structure was a seed and so based on in my lab actually they didn't previous study and they look to see if these structures could float in saltwater and they can for like months.
Interviewer: Oh so they would maybe leave the island.
Hana: So what we think is probably that seeds from the mainland got into the water and were carried down to the islands.
Interviewer: Right okay so then that would count as its colonization.
Hana: Yeah Exactly.
Hana: But because of that that's one reason why bromion blada could could have been prone to founder effect 'cause if you have one seed that's one individual colonizing that island.
Interviewer: Right yeah that's interesting um so how were you measuring the genetic diversity of these plant species?
Hana: So I took leaf tissue and then we extracted DNA and then we had nine genes that we sequenced using Sanger sequencing and then so we were just looking so we had about five individuals per population we had a bunch of different mainland populations and then populations on the islands member 5 individuals for population per populations so we could look at each gene and see differences between individuals of the same population see if they had different versions of those genes to sort of get an idea of their genetic diversity.
Interviewer: Interesting okay um so you sound pretty passionate about this topic which is fair is very interesting but what specifically makes you passionate about this area of study?
Hana: Yeah so I've always been like interested in nature always loved nature and being outside it was camping a lot as a kid have always loved animals so for me I knew I always wanted to go into biology like that was never really a question and then as i got older and started learning more about environmental issues like endangered species and climate change I wanted to get into the environmental side of it too I knew I wanted to protect nature and life on earth so I was always sort of interested in animals I didn't really think about plants so much until I met the Prophet I did this thesis with an sort of started learning more about plants and they're actually really fascinating really cool to study because they are sessile they could only stay in one place so they have to have sort of a wide range of abilities to deal with changes in their environment 'cause if the environment isn't favorable they can't just like get up and leave so built into their genome is all these different ways of dealing with basically every environment on earth you can find plants wow they're also really cool and a little easier to study than animals in certain ways because you can have like a lot of replicates you could plant a whole bunch of plants and have them in one greenhouse you know hundreds of plants or is this a lot harder to do with animals you can't just stop them all in a cage and so they really cool to study for that reason and yes those kind of how I got into it and as I start getting into more into genetics I just found out that really interesting and the aspect of conservation genetics were looking at populations that we may be losing genetic diversity and unable to respond to changes in the environment and that that was all very cool.
Interviewer: And is that probably made worse by climate change too?
Hana: Yeah for sure so um as plants or most species in general as the globe warms species are getting pushed North so in order for them to adapt they're going to have to either adapt where they are or they have to be able to shift their range northwood northward and so you can imagine this founder effect could be happening as there like moving North alright so that could potentially be losing genetic diversity as they moved North also this is already happening in obroni on vilada too we're seeing population in the southern portion of its range just like disappearing we went we went back to populations that were there 10 years ago and couldn't find them.
Interviewer: Wow really concerning and that's ten years
Interviewer: Oh my goodness yeah.
Hana: And of course in Southern California and Baja Mexico they've been going through a big drought so maybe this is just a bad year or a bad 10 years maybe they’ll bounce back or maybe not its hard to tell but based on past genetic studies we know that there was a lot of unique very genetic variation in these southern populations that could be lost and so that is not great for the species as a whole.
Interviewer: Wow so like some extinction of certain variations.
Hana: Exactly yeah once they're gone that is so hard to get back almost that specific mutation happens again the giant which are very very unlikely.
Interviewer: 'cause it's kind of is it a function of evolution sort of? so that would take really long time.
Interviewer: Yeah exactly that's so sad yeah the tragedy of the bronia.
Interviewer: Um so were you in the end able to concretely determine how colonization affected obroni balada and is this research ongoing.
Hana: Yeah so we had it we came up with answers as a lot of things in nature or in biology study of biology nature doesn't really fit into a box all that great so for obroni balada anyway genetic diversity on the islands wasn't much lower than on the mainland which was interesting maybe maybe just it was just the jeans were looking at we only looked at 9 in the whole genome so maybe there's a loss of genetic diversity in other genes we don't really know as far as we also looked at genetic differentiation so see if there's different versions of those jeans on the island then on the mainland so for two of the islands we looked at they were quite similar to the mainland but one island was really differentiated which was really interesting and that island was also the smallest and farthest away so it makes sense that it could be the most isolated the two that were similar to the mainland or closer to the mainland and bigger they also have more human traffic so it's possible that there could be some mixing with populations on there.
Hana: But yes St. Nicholas which is the smallest and most isolated is also quite genetically differentiated which was really cool but I'm running a lot of grows on six of the Channel Islands and we were only able to look at three so we can't really speak for all of them as a whole right so we are going to try and get samples from the other islands to see if we can kind of finish that.
Interviewer: Cool well that was super super interesting I learned quite a bit about plants and genetic variation and yeah that's super cool thank you so much for joining us Hana.