Do you fancy doing plant science off the shores of Tasmania, around the Antarctic, or even Hawaii? Then the Zooniverse has the project for you. Floating Forests is a website to study the growth or decline of giant kelp, Macrocystis around the world.
Giant kelp is pretty well named. It can grow to sixty metres in length and it is found around the world. The undersea forests they make are vital habitat for many other species. So tracking growth or decline would be a good thing. The difficulty is that you simply cannot dive everywhere to examine the forests up close – and this is where the Zooniverse comes in.
The Zooniverse site was set up to have the public classify galaxies at a site called GalaxyZoo. Astronomers knew humans were much better at recognising what sort of galaxies they were looking at than computers. The average member of the public wouldn’t be as good as a professional astronomer, but ask enough and you can average out all the errors and get a result better than one professional classifying galaxies. They also found you got results faster, because there’s plenty of people willing to help with primary science.
Floating Forests works in a similar way, but instead of looking out from Earth to space, the Floating Forests images are taken from orbit looking at Earth.
To take part you first sign up. Then you can see a tutorial on how to mark up images, but it’s basically drawing loops around what you think is kelp.
Your eyes might be better than mine, and you might see more kelp in the images. Or maybe I was trigger happy and marked too much. Averaging will help factor out mistakes similar to the concept of The Wisdom of Crowds.
The images are from Landsat. It means the any individual image could be lousy. There are corrupted images, some which are just land or sea and plenty that are clouded out. They have tools for working round this. The upside of using Landsat data is that there’s an archive going back thirty years, so while a place might be clouded out one month, it’s not likely to be covered all the time. It opens the potential for detailed analysis by season and over time.
The project is a collaboration between the Zooniverse and the Kelp Ecosystem Ecology Network, and they’re running a blog to keep people up to date with what they’re finding. The Zooniverse has been terrific in getting people engaged with astronomy. With luck, KEEN can do the same for marine ecology.
Photobiont selectivity leads to ecological tolerance and evolutionary divergence in a polymorphic complex of lichenized fungi
The integrity and evolution of lichen symbioses depend on a fine-tuned combination of algal and fungal genotypes. Geographically widespread species complexes of lichenized fungi can occur in habitats with slightly varying ecological conditions, and it remains unclear how this variation correlates with symbiont selectivity patterns in lichens. In an attempt to address this question, more than 300 samples were taken of the globally distributed and ecologically variable lichen-forming species complex Tephromela atra, together with closely allied species, in order to study genetic diversity and the selectivity patterns of their photobionts.
The presence of a below-ground neighbour alters within-plant seed size distribution in Phaseolus vulgaris
Considerable variation in seed size commonly exists within plants, and is believed to be favoured under natural selection. This study aims to examine the extent to which seed size distribution depends on the presence of competing neighbour plants. Below-ground neighbour presence affects within-plant seed size distribution in P. vulgaris. This effect appears to be non-resource-mediated, i.e. to be independent of neighbour-induced effects on resource availability. It implies that, based on current environmental cues, plants can make an anticipatory adjustment of their investment strategy in offspring as an adaptation to the local environment in the future.
Extensive long-distance pollen dispersal and highly outcrossed mating in historically small and disjunct populations of Acacia woodmaniorum (Fabaceae), a rare banded iron formation endemic
Understanding patterns of pollen dispersal and variation in mating systems provides insights into the evolutionary potential of plant species and how historically rare species with small disjunct populations persist over long time frames. This study aims to quantify the role of pollen dispersal and the mating system in maintaining contemporary levels of connectivity and facilitating persistence of small populations of the historically rare Acacia woodmaniorum.
An angiosperm-wide analysis of the gynodioecy-dioecy pathway
About 6 % of an estimated total of 240 000 species of angiosperms are dioecious. The main precursors of this sexual system are thought to be monoecy and gynodioecy. A previous angiosperm-wide study revealed that many dioecious species have evolved through the monoecy pathway; some case studies and a large body of theoretical research also provide evidence in support of the gynodioecy pathway. If plants have evolved through the gynodioecy pathway, gynodioecious and dioecious species should co-occur in the same genera. However, to date, no large-scale analysis has been conducted to determine the prevalence of the gynodioecy pathway in angiosperms. In this study, this gap in knowledge was addressed by performing an angiosperm-wide survey in order to test for co-occurrence as evidence of the gynodioecy pathway.
Arrangement of mixed-linkage glucan and glucuronoarabinoxylan in the cell walls of growing maize roots
Plant cell enlargement is unambiguously coupled to changes in cell wall architecture, and as such various studies have examined the modification of the proportions and structures of glucuronoarabinoxylan and mixed-linkage glucan in the course of cell elongation in grasses. However, there is still no clear understanding of the mutual arrangement of these matrix polymers with cellulose microfibrils and of the modification of this architecture during cell growth. This study aimed to determine the correspondence between the fine structure of grass cell walls and the course of the elongation process in roots of maize.
Cold hardiness of Brachypodium distachyon accessions
Brachypodium distachyon is considered a powerful model system to study the response of temperate cereals to adverse environmental conditions. Colton-Gagnon et al. examine cold acclimation and freezing tolerance in seven diploid accessions, and find that cold treatment accelerates the transition from the vegetative to the reproductive phase in all of them. This is associated with the gradual accumulation of BradiVRN1 transcripts, and the accessions exhibit a clear cold acclimation response by progressively accumulating proline, sugars and COR gene transcripts. However, whole-plant freezing tests show that the accessions only have a limited capacity to develop freezing tolerance when compared to winter varieties of temperate cereals such as wheat and barley. Furthermore, little difference in terms of survival is observed among the accessions tested despite their previous classification as either spring or winter genotypes.
The Indian Botanists have a review of ‘Green Wars- Dispatches from a Vanishing World’ by Bahar Dutt as well as an interview with her about the book.
Bibliodyssey, the art history blog, has a post on pomology and some illustrations from the 19th century.
Via Anne Osterrieder, there are the most well-referenced Frozen parodies I’ve seen, with New Under The Sun Blog’s post, Do you want to make a plastid? and For the First Time in Forever: Vernalization
I’ll assume you’ve already seen the Agricultural Biodiversity Weblog’s Nibbles.
Growth and cellular patterns in petal epidermis of Antirrhinum
Analysis of cellular patterns in plant organs provides information about the orientation of cell divisions and predominant growth directions. Raczyńska-Szajgin and Nakielski study patterns in the epidermis of asymmetrical wild-type dorsal petals and symmetrical dorsalized petals of the backpetals mutant of Antirrhinum majus (snapdragon) to determine how growth in initially symmetrical petal primordia leads to the development of mature petals differing in their symmetry. They find that during primordia development a characteristic fountain-like cellular pattern is maintained with only slight modifications, and petal cells divide in non-random directions. These features of the cellular pattern are presumably related to principal directions of growth. Two scenarios are considered to explain how gradual modifications in these directions may contribute to the transition from a symmetric to an asymmetric cellular pattern in the wild type petal.
Water deficit effects on structure of proleptic and epicormic shoots
Shoot characteristics differ depending on the meristem tissue that they originate from and the environmental conditions during their development. Negrón et al. observe and model the effects of plant water status on axillary meristem fate and flowering patterns along proleptic and epicormic shoots of almond trees, Prunus dulcis. They find that the two shoot types differ in their patterns of axillary meristem fates along the shoot, and in their axillary meristem fate responses to water stress. The structure of proleptic shoots is more sensitive to water stress than epicormic shoots and reflects differences in their ontogenetic status as well as growth rate patterns during the season.
Clonal spread influences genetic structure and diversity in plant populations as well as their realized outcrossing rate. Using microsatellite markers, Somme et al. investigate genetic diversity and the effect of clone distribution, structure and size on the mating of bee-pollinated marsh cinquefoil, Comarum palustre (Rosaceae), which is a rare, self-compatible species that grows in endangered European wetlands.
They find that clones are spatially clumped, with intermediate to no intermingling of the ramets, and large clones show lower outcrossing rates than small clones. Pollen dispersal mainly occurs within patches with very few pollination events occurring between patches of more than 25 m separation.These factors need to be taken into account in management strategies for ensuring population persistence.
A collection of papers on Extrafloral Nectaries has recently moved into Free Access at Annals of Botany. One of the papers raises the question, can a plant that never flowers have extrafloral nectaries?
Photo: Koptur et al.
Nectar secretion on fern fronds associated with lower levels of herbivore damage: field experiments with a widespread epiphyte of Mexican cloud forest remnants by Koptur et al. examines why ferns produce nectar. The paper starts with a brief review which includes a few facts that startled me. One is that extrafloral nectaries evolved before floral nectaries. This surprises me because I so deeply associate nectar with flowers. Another shock was that nectaries appear on ferns well before ants appear in the fossil record.
This shouldn’t be a surprise, but we’re so used to evolutionary stories being teleological, like plants evolved nectaries to reward insects, that it’s easy to forget that it’s a huge oversimplification that gets things very wrong. Nectaries didn’t evolve in order to do something with a purpose. Instead that plants with nectaries have a better chance of passing their traits to their offspring because they can reward insects. And what if there are no insects? Koptur et al. say that the early appearance of nectaries supports the ‘leaky phloem’ hypothesis, that sugars are forced out of the plant in weak developing tissues to ease hydrostatic pressure in the plant. This might explain how they formed, but once ants arrived did they help select ferns with better nectaries. Do the nectaries in ferns given them an evolutionary advantage?
The nectaries are on the leaves or fronds of the plant. Developing fronds are a prime target for herbivores, so if the ants were drawn into the leaves they could act as a defence. But do they. The experiment, like many of the best ones, sounds quite simple.
At its simplest, you find a plant with a suitable pair of young fronds. On one you paint over the nectaries with nail polish to prevent access to the nectar. You then see how the plants develop and compare the damage on the untreated leaf with the test leaf. Reality is messy, so they actually did a lot more than that to account for other factors – but the basic experiment was does access to the nectaries matter?
The results were clear. The fronds with blocked nectaries had four times the damage of the untreated fronds. The ferns benefited from hosting plants, and the ones that could attract them best got the best defence. The defence works best against invasive species that haven’t co-evolved with the fern and developed counter-defences against the ants.
It’s easy to see nectar as part of the plant’s reproductive strategy, or maybe as part of the reproductive system that’s been repurposed for something else. I think this paper neatly shows that there’s no need to assume any connection at all. There’s a lot more to nectar than bait for pollination.
Quora is a site for posting questions to the internet. Sometimes those questions get answer. For example Robert Frost, who has trained astronauts for the International Space Station, has answered the question: How are plants growing in the ISS?
Gravity is not the only difference between the Earth environment and the ISS environment. In the closed atmosphere of a spacecraft, volatile organic compounds (VOCs) can accumulate. VOCs need to be scrubbed from the air or seed production will suffer. There are elevated radiation levels that can cause mutations and affect growth. An experiment on Mir, that involved storing tomato seeds in space for six years found mutation rates up to 20 times higher in the space seeds than in the control seeds stored on the ground. And there are the spectral effects of using only electric lighting.
An autotrophic astronaut. Photo: NASA.
Because plants also respire, we have to have fans to circulate the air around the plants so that they don’t suffocate on their own exhalations. Even failed experiments can provide us with better understanding. An experiment to study plant lignin failed to produce healthy plant materials but taught us more about providing effective air movement.
You can read more at Quora.
Annals of Botany had an editorial meeting recently one of the topics that came up was how can authors increase the readership of their paper? One place that can have a surprisingly large impact is the abstract.
If you’ve spent an age trying to get all the details of your research right, it can be painful reducing everything to a couple of hundred words. However an abstract isn’t a mini-version of your paper, it’s a tool to get people to read your paper, and that means making it as easy as possible for people to see why they should care. There’s the full slidedeck up at Haiku Deck or press play above.