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2017 update: Reproductive fitness in remnants

Successful pollination leads to full achenes and higher fitness later in the season!

This summer we counted shriveled and non-shriveled rows of styles three times per week for every Echinacea head in 8 of the 28 remnant populations. We also harvested 121 Echinacea heads to be analyzed for seedset data. This year we selected heads for harvest based on their position within randomly selected plots where Tracie Hayes and Lea Richardson collected vegetation data. In every randomly selected vegetation plot, all species were identified and we recorded their abundance. We marked any Echinacea head within a vegetation plot for harvest. Harvested heads are ready to be processed by citizen scientists at the Chicago Botanic Garden. In the lab, heads will be cleaned so that all achenes can be counted and x-rayed to determine seedset.

Measuring the reproductive success of an Echinacea angustifolia head gives insight into the fitness of the individual. In remnant populations, we measure reproductive success using two methods: style persistence and seedset. Seedset is the proportion of all seeds that are viable in an Echinacea head, and is measured in the lab after heads have been harvested. Style persistence is a fitness measure that can be taken during the field season. Styles, the showy female reproductive structures that emerge from every floret in an Echinacea head, shrivel within 24 hours if they receive compatible pollen. Keeping track of how many styles shrivel and how many persist can give us a sense of the reproductive success of that head without any lab work.

Year: 1996

Location: Roadsides, railroads and rights of way, and nature preserves in and near Solem Township, Minnesota.

Overlaps withflowering phenology in remnantsmating compatability in remnants

Physical specimens: 121 harvested heads, currently at the Chicago Botanic Garden

Data collected:

  • Style persistence data for each flowering head, collected three times per week, stored in remData
  • Dates and identities of harvested heads, stored on paper datasheets entered electronically into richHood

GPS Points Shot: A point for each flowering head, stored under PHEN and SURV records in GeospatialDataBackup

Products:

 

You can find out more about reproductive fitness in the remnants and read previous flog posts about it on the background page for the experiment.

 

 

 

2016 Update: Reproductive fitness in remnants

Alex and Leah with one of the first flowering plants of the season!

One of many visits to each flowering plant in prairie remnants.

Assessing fitness is a key part of understanding change in any population. The Echinacea Project has focused on two quantifiable components of reproductive fitness of Echinacea angustifolia: style persistence and seed set. Styles shrivel when they receive compatible pollen, and thus persistence of styles reflects pollen limitation. A floret sets a seeds only when it has been successfully pollinated. Together, these two indicators can be used to predict how effectively individual plants produce viable offspring, giving insights into the persistence of remnant populations.

This year, we counted shriveled and non-shriveled rows of styles on each flowering head of every plant in 28 remnants three times per week. Well after the flowering season, we harvested 104 heads at a subset of these sites. The harvested heads will have their achenes removed, counted, and x-rayed by citizen science volunteers to estimate how many seeds they produced. There were several concurrent projects this summer and in the lab that use these measures, including Amy Waananen’s compatibility study and James Eckhardt’s study of edge effects.

Year: 1996

Location: Roadsides, railroads and rights of way, and nature preserves in and near Solem Township, Minnesota.

Overlaps with: flowering phenology in remnants, mating compatability in remnants

Physical specimens: 104 harvested heads, currently at the Chicago Botanic Garden

Data collected:

  • Style persistence data for each flowering head, collected three times per week, stored in remData
  • Dates and identities of harvested heads, stored on paper datasheets in Harvest 2016 binder and entered electronically into remData

GPS Points Shot: A point for each flowering head, stored under PHEN and SURV records in GeospatialDataBackup

Products:

 

You can find out more about reproductive fitness in the remnants and read previous flog posts about it on the background page for the experiment.

Emma and Mikaela Are on the Case

So it begins! Two new externs have joined Team Echinacea from Carleton College. We (Mikaela and Emma) will be here every day for the next three weeks, and are excited to discover new revelations for the Asynchrony, Isolation and Incompatibility experiment.

So far, most of what we’ve discovered is that cleaning Echinacea seed heads is tedious. Two days in, we have cleaned 36 seed heads; scanning them was a nice relief from the monotony. We think we could get through all 110 by the end of this week.

Although yesterday was quiet, there was a little bit of commotion: Mikaela’s second seed head had a rare deformity. Many of the achenes were uninformative. This means they were aborted part of the way through formation, so it cannot be determined whether they were fertilized. After minutes of puzzled deliberation, Stuart, Amy and Scott decided to keep them in the sample.

Four uninformative achenes compared to one normal, mid-size achene. Because of their immaturity, the florets are still firmly attached.

Four uninformative achenes compared to one normal, small-to-mid-size achene. Because of their immaturity, the florets are still firmly attached.

In contrast to yesterday, today there were quite a few volunteers and a couple of students who we got to meet. It was nice to talk to other people who were involved in and excited about this project. We also got to hear about other experiments going on in the lab besides our own.

Today’s seed cleaning also presented an exciting moment: just moments after Amy told us about last year’s larval discoveries, we each found a live larva residing in the heads we were cleaning. We’re thinking about raising these mystery larva so we can finally learn just what they are. Hopefully we’ll have more success than last year’s effort!

Our two larva. Emma's is the tiny brown one on the right, and Mikaela's is the pink one hanging out on a makeshift habitat of chaff.

Our two larva. Emma’s is the tiny brown one on the right, and Mikaela’s is the pink one hanging out on a makeshift habitat of chaff.

We are grateful for this opportunity to contribute to and learn from the project, and are looking forward to the next three weeks!

Thanks for the warm welcome,

Mikaela and Emma

 

Chicago: No Phone, $1.00 Edition

Part 1. I couldn’t stay away from the Echinacea Project too long. As I’m positive you want to hear both about my poster that I will be presenting at MCMS tomorrow at the University of Chicago and my adventures in Chicago, I will share both. As I arrived at the airport to fly to Chicago, I realized I had forgotten my cell phone. I thought to myself, I lived most of my life without a cell phone, I can do it another day. After arriving in Chicago, I had thankfully packed a dollar in quarters, so I was able to use a pay phone (yes, those still exist) to call a cab. While I did struggle to understand the technology, I was finally able, after spending my only dollar in quarters, to procure transportation to the Chicago Botanic Gardens. I was left penniless, phoneless, and with only a laptop and my knowledge of Chicago (this, by the way, was absolutely nil). After making a successful rendezvous with the team, I enjoyed a lunch and tour of the lab. It was great to see everyone again.

Part 2. After figuring out the best way to get to my destination at the University of Chicago, I jumped on the purple line, confident that, after a quick jaunt on the green line, all I’d have to do was walk a block or two to the hotel, where dinner awaited me. I hopped off the train, and quickly realized that the area had been highly developed since the last google street image had been taken, unless my memory of the picture failed me. Ah well, I thought, I wrote down the street that will get me to my hotel, it’s just east of here. The street just east was not the correct street. Maybe the map I saw was just wrong. By the next street, I knew I was in the wrong place. Thankfully a friendly man suggested a bus that would take me five miles to the east, where I thought I was getting off. Yes, I had taken the wrong train. All was well and good until I hopped on the bus and realized that I was penniless, with no money for a fare. Again, the bus driver was a greatly friendly man, and I rode the bus without a fare. Sailing was smooth from there on out.

Tomorrow I will present my findings on how edge effects play a role in the style persistence and pollen limitation of Echinacea at the Midstates Consortium for Math and Science. Style persistence decreased as plants were farther from habitat edges, demonstrating a spatial pattern in pollination. Attached is my poster. stylepersistenceedgeposter

Off to share a room with someone I haven’t met yet. Day in the life.

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No explanation needed. Great to see y’all again.

Some Light Reading for Your Sunday Afternoon

I am excited to present to you my summer 2016 research proposal. While previous research has shown that isolated Echinacea plants and populations experience reduced reproductive fitness, we have not looked at what influence edge effects may have on Echinacea populations. Findings presented in Ison and Wagenius 2014 showed that plants in P1 experienced slight edge effects on seed set. My research this summer will use style persistence data collected from all remnant sites and quantify the relationship between distance of an Echinacea plant from a habitat edge and average style persistence. This will help us understand if fragmented populations are being harmed by yet another factor. Hopefully you find this topic as interesting as I do.

JamesEckhardtProposal2016

Project status update: The mating scene (remnant asynchrony, isolation, and incompatibility)

This project investigates the role of three fundamental constraints on mate availability – temporal asynchrony, spatial isolation, and reproductive incompatibility – in remnant Echinacea angustifolia populations. During the summer of 2014, we conducted two studies related to The Mating Scene project. In the first study, we mapped 991 Echinacea plants and monitored the phenology of 1360 flowering heads across 31 remnants to quantify spatial isolation and flowering asynchrony. At the end of the season, we harvested 193 flowering heads from 25 remnants to assess seed set. In the second study, we performed 364 pollen crosses to characterize patterns of reproductive incompatibility within 10 remnants. With the data collected in 2014 and subsequent years, we aim to elucidate how the interactions between temporal asynchrony, spatial isolation, and reproductive incompatibility influence reproductive fitness in fragmented prairie remnants.

site # of flowering plants # of flowering heads # of crosses # of heads harvested
1 aa 60 83 36 5
2 alf 63 78 6
3 btg 3 3 2
4 dog 1 2
5 eelr 33 17 28 5
6 eri 38 54 5
7 eth 9 46 5
8 gc 6 6 3
9 kj 7 8 5
10 lce 90 70 24 5
11 lcw 51 95 24 5
12 lfe 64 103 24 5
13 lfw 89 57 24 6
14 ngc 8 5
15 nnwlf 2 13 5
16 nrrx 20 25 5
17 nwlf 13 16 5
18 on27 92 96 42 5
19 ri 82 112 44 5
20 rrx 43 47 33 5
21 rrxdc 3 3 2
22 sap 29 13 5
23 sgc 8 243 5
24 SppE 92 81 41 42
25 SppW 51 38  44 42
26 th 8 9 5
27 tower 7 11 5
28 waa 4 8
29 wood 4 4
30 yohE 4 5
31 yohW 7 9

Start year: 2014

Location: Phenology in 31 total remnants, compatibility in 10 remnants

Products: The phenology and compatibility datasets need to be made readyR. The harvested flowering heads are being processed at the Chicago Botanic Garden.

Overlaps with: phenology in six remnants, fire and flowering at SPP