Thursday, February 14, 2008
Wednesday, February 13, 2008
botany related link
www.botany.com/ - 9k -
Botany - Wikipedia, the free encyclopedia
Botany is the scientific study of plant life. As a branch of biology, it is also called plant science(s), phytology, or plant biology. Botany covers a wide ... en.wikipedia.org/wiki/Botany - 90k - |
Careers in Botany - Science Education and Outreach, Botanical ...
Science Careers - Science Education and Outreach, Botanical Society of America. www.botany.org/bsa/careers/ - 51k - |
Botanical Society of America - Leading Scientists and Educators ...
Botanical Society of America - Leading Plant Scientists and Educators Since 1893, plant science, research, education, outreach. www.botany.org/ - 49k - |
World-Wide Web Virtual Library: Botany / Plant Biology (Biosciences)
Collection of scholarly and research links for plant biology. www.ou.edu/cas/botany-micro/www-vl/ - 48k - |
Botany Photo of the Day
Thank you to Michael Charters of Calflora.net for contributing today's photograph via the Botany Photo of the Day submissions forum on the garden's site (in ... www.ubcbotanicalgarden.org/potd/ - 37k - |
Botany in the Yahoo! Directory
Learn about botany and various plant species through sites dedicated to trees, roses, orchids, wild flowers, cactuses, herbs, tropical plants, ... dir.yahoo.com/Science/Biology/Botany/ - 16k - |
Internet Directory for Botany
The Page Lists All Pages/Sites Related to Botany: Plant Science, Gardens, Gardening, Forest, Biology, Plant Physiology, Plant Taxonomy, Plant Systematics, ... www.botany.net/IDB/ - 8k - |
Botany Net
Botany Net. Internet Directory for Botany · List of WWW Sites of Interest to Ecologists(mirror) www.botany.net/ - 1k - |
Google Directory - Science > Biology > Botany
Contains more than 2500 terms relating to botany, gardening, horticulture and landscape architecture. Fully searchable and it is regularly updated. ... www.google.com/Top/Science/Biology/Botany/ - 21k - |
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botany related link
dir.yahoo.com/Science/Biology/Botany/ - 16k -
Internet Directory for Botany
The Page Lists All Pages/Sites Related to Botany: Plant Science, Gardens, Gardening, Forest, Biology, Plant Physiology, Plant Taxonomy, Plant Systematics, ... www.botany.net/IDB/ - 8k - |
Botany Net
Botany Net. Internet Directory for Botany · List of WWW Sites of Interest to Ecologists(mirror) www.botany.net/ - 1k - |
Google Directory - Science > Biology > Botany
Contains more than 2500 terms relating to botany, gardening, horticulture and landscape architecture. Fully searchable and it is regularly updated. ... www.google.com/Top/Science/Biology/Botany/ - 21k - |
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Categories
Algae
October 27, 2007
Codium fragile subsp. tomentosoides
Thank you to Courtnay H, aka Seaweed Lady@Flickr, for sharing today's photograph (original image via BPotD Flickr Group Pool. If you love the sea and plants (like me), you certainly should view Courtnay's photographs on Flickr.
Courtnay suggests the following link to accompany her photograph: Codium fragile subsp. tomentosoides via Algaebase. If you visit that page, the word “weed” is used (Courtnay calls this photograph “beautiful invader”); indeed, this species is listed in the Global Invasive Species Database, with a comprehensive list of common names: dead man's fingers, green fleece, green sea fingers, oyster thief or Sputnik weed. Originally from Japan, it is now found in many temperate waters worldwide, its dispersal due to “shellfish aquaculture, recreational boating, and transport on ship hulls”.
The common name of oyster thief is due to this alga's tendency to proliferate in shellfish beds, where it can smother the shellfish with its rapid growth and colonial expansion. Sputnik weed is, as you might guess, a fifty year old common name from eastern North America. The introduction of this species to eastern North American waters was first observed around the same time as the launch of the Soviet Union's satellites.
Posted by Daniel Mosquin at 12:00 AM | Comments (2)
September 23, 2007
Pelvetia canaliculata
Botany Photo of the Day will have brief written entries on weekends, holidays and my vacations from April through September. – Daniel
Another nod of appreciation to Stephen B of Scotland aka stephenbuchan@Flickr for sharing today's photograph (original via the BPotD Flickr Pool). Thank you!
Channelled wrack can be found in the high intertidal zone on rocky shores of Atlantic Europe (e.g., in the United Kingdom).
Wikipedia has a tidy summary of Pelvetia canaliculata.
Posted by Daniel Mosquin at 12:00 AM | Comments (5)
July 05, 2007
Unidentified Algae
Botany Photo of the Day will have brief written entries on weekends, holidays and my vacations from April through September. – Daniel
Today's image is courtesy of bbum@Flickr, aka Bill from San Jose, California (original via BPotD Flickr Group Pool). Thank you!
If you'd like a challenge, try identifying this species of alga (I wasn't able to do it with an hour of searching, but then again, I'm not a phycologist!).
Posted by Daniel Mosquin at 12:00 AM | Comments (4)
June 22, 2007
Postelsia palmaeformis
Botany Photo of the Day will have brief written entries on weekends, holidays and my vacations from April through September. – Daniel
Sea palms are one of the few algae covered in-depth on Wikipedia: Postelsia palmaeformis. Like Pelvetiopsis limitata, it is found from the coasts of northern Vancouver Island to the coastal waters of mid-California.
This is the last photograph in the current series on algae. For the definitive photograph of sea palms, see this image of sea palms by Wynn Bullock (one of my all-time favourites).
Posted by Daniel Mosquin at 12:00 AM | Comments (2)
June 21, 2007
Laminaria setchellii
I've mentioned in a previous BPotD entry that the waters of the northeast Pacific contain more species of kelp than anywhere else in the world. Today's photographs illustrate another member of that diverse group, southern stiff-stiped kelp (by the way, there are no search engine results for northern stiff-stiped kelp, so I think stiff-stiped kelp should suffice as a common name). Ecologically, this alga grows from the low intertidal zone on open rocky shores to complete submergence, where it can sometimes be an understory species in kelp forests.
Decew's Guide once again provides some background and references: Laminaria setchellii. The photo gallery at Algaebase provides a more conventional presentation of this species, if you'd like to investigate.
Posted by Daniel Mosquin at 12:00 AM | Comments (6)
June 20, 2007
Ulva intestinalis
Today's photographs and write-up are courtesy of Douglas Justice, UBC Botanical Garden's Curator of Collections. This is the second in a series of at least four BPotD entries on algae.
Ulva intestinalis is pictured here attached to smooth basaltic rock in brackish water on MacKenzie Beach, just north of Pacific Rim National Park. This species is a common feature of tidepools around the world, where it is known variously as sea hair or (more appropriately) gut weed. An annual species, local beaches are littered with their bleached, dried-up stems as temperatures fall in the autumn.
Daniel adds: Note that many references will have this algae under the name Enteromorpha intestinalis (L.) Nees, e.g., DeCew's Guide. For a long time, Enteromorpha was considered a distinct genus from Ulva, based mainly on its tubular growth form. The two genera have now been merged; see Hayden et al. 2003. Linnaeus was right all along: Ulva and Enteromorpha are not distinct genera. (PDF) European Journal of Phycology. 38: 277-294.
Posted by Daniel Mosquin at 06:10 AM | Comments (1)
June 19, 2007
Pelvetiopsis limitata
I revisited Botanical Beach on the weekend, in what I hope becomes an annual trip for me – it's one of my favourite places in the world. I found it strange that I and my companion were the only ones on the beach on early Saturday morning; I thought the attraction of seeing a zero tide, one of the lowest tides of the year here, would lure more people. More people did visit eventually, but it was perhaps an hour after the zero tide mark before we saw the first few, with numbers gradually increasing after that.
Pelvetiopsis limitata is distributed along the west coast of North America, from northern Vancouver Island to the mid-California coast in San Luis Obispo County. One curious morphological variation that occurs from north to south is an increase in the density of surficial hairs, such that the individuals in California are covered in fine hairs. Jennifer Skene of UC Berkeley is researching the origin, formation and function of these hairs, and whether they might have an impact upon buffering the effects of climate change.
Decew's Guide at the Center for Phycological Documentation contains a guide page about Pelvetiopsis limitata, including journal references associated with each of the facts (very handy). The Multi-Agency Rocky Intertidal Network has more photographs of this species in its factsheet on Pelvetiopsis limitata.
Posted by Daniel Mosquin at 06:03 AM | Comments (6)
October 17, 2006
Trentepohlia aurea (tentative)
Another thank you to brettf@Flickr for sharing a macro glimpse of an organism (original image). Also, a thank you to GORGEous nature@Flickr for identifying it, since I didn't know about this organism before today. A second image by Brett can be seen here that gives a more distant perspective. Thank you!
Despite its colour, Trentepohlia is actually a green alga. The chlorophyll pigment is masked by the presence of large amounts of β-carotene, the same photosynthetic pigment that causes the orange colouration of most carrots.
The appearance of Trentepohlia so closely resembles a lichen that it warrants a line in the lichen identification keys for British Columbia – a very astute decision, in my opinion.
Read more about this alga at the University of Paisley's Biodiversity Reference page for Trentepohlia (includes microscopic photographs!).
Posted by Daniel Mosquin at 05:50 AM | Comments (5)
August 15, 2006
Halosaccion glandiforme
I'm glad that a few photographs turned out from my weekend trip to Vancouver Island. Otherwise, I'd be even more cross at the one hour delay for one ferry (on the way there) and the four and a half hour delay on the way back. I didn't get home until 4 AM Monday morning; 4 AM was also the time I started on Sunday to reach Botanical Beach at low tide, the site of today's photograph.
Sea sacs are an algae of the intertidal zone, the area between the high tide mark and the low tide mark. The narrow band of the intertidal requires its inhabitants to have developed a number of strategies or structures to survive in this harsh area; mechanical pounding of the surf, temperature and moisture fluctuations and salinity variability are just a few of the conditions requiring special adaptations.
As noted in this essay on Halosaccion glandiforme, one adaptation of this alga to live in the intertidal is its gross morphology. The short, tubular shape of sea sacs helps to prevent damage from churning water. A second adaptation is the ability of sea sacs to retain water internally in the sac, moderating the extremes of temperature and moisture that would otherwise be experienced by the organism.
More photographs of Halosaccion glandiforme can be seen on California Biota and Seaweeds of Alaska.
Posted by Daniel Mosquin at 12:00 AM | Comments (5)
April 18, 2006
Macrocystis pyrifera and Ardea alba
Beds of giant kelp (Macrocystis pyrifera) provide a floating platform for the piscivorous (fish-eating) great egret in the marine waters of California's Point Lobos State Reserve. What you see from above the water as tangled mats of seaweed are the uppermost fronds of organisms which may reach heights of 60m (read more on Macrocystis pyrifera). In favourable areas, dense, underwater kelp forests form; these support a wide diversity of other organisms. For an excellent summary article on the biology of kelp forest ecosystems, see Steneck, R. et al. 2002. Kelp Forest Ecosystems: Biodiversity, Stability, Resilience and Future. Environmental Conservation. 29:436-459.
Kelps, or the Order Laminariales, are most diverse in the coastal waters of the temperate northeastern Pacific Ocean, with twenty species occurring from Alaska to Baja California.
Botany resource link: Plant for the Planet: A Plant Conservation Checklist for Gardeners (PDF file), a small brochure on gardening with plant conservation in mind from Botanic Gardens Conservation International – Canada.
Posted by Daniel Mosquin at 12:00 AM | Comments (3)
August 11, 2005
Fucus gardneri
A strong contender for the plant (note: see comments below - not actually a plant, but a stramenopile) with the “most common” common name, common rockweed is a brown alga typically found in the intertidal zone of rocky shorelines. It is abundant throughout the temperate waters of the Pacific Northeast, from California to Alaska.
For more information about this plant stramenopile, see Fucus gardneri on the Center for Phycological Documentation site for a wide array of references.
Algae are a large and diverse group of simple plant-like organisms, ranging from unicellular to multicellular forms. The largest and most complex marine ...
en.wikipedia.org/wiki/Algae - 116k -
Green algae - Wikipedia, the free encyclopedia
The green algae (singular: green alga) are the large group of algae from which the embryophytes (higher plants) emerged. As such, they form a paraphyletic ... en.wikipedia.org/wiki/Green_algae - 35k - More results from en.wikipedia.org » |
Algae Research/ Department of Botany, National Museum of Natural ...
Algae are photosynthetic organisms that occur in most habitats. They vary from small, single-celled forms to complex multicellular forms, such as the giant ... www.nmnh.si.edu/botany/projects/algae/ - 7k - |
The world of algae
Some people treat algae as a subkingdom under the Whittaker 5-kingdom system of classification. This violates all the principles of modern systematics, ... www.botany.uwc.ac.za/algae/ - 22k - |
ALGAE
Many of the larger algae are accepted as plants by most people but the absence of highly differentiated cells distinguishes them from the kingdom Plantae ... hcs.osu.edu/hcs300/algae.htm - 10k - |
Introduction to the Green Algae
The "green algae" is the most diverse group of algae, with more than 7000 species growing in a variety of habitats. The "green algae" is a paraphyletic ... www.ucmp.berkeley.edu/greenalgae/greenalgae.html - 5k - |
UNH Biodiesel Group
Michael Briggs describes how much biodiesel would be needed to replace all petroleum transportation fuels in the United States and how algae could be used ... www.unh.edu/p2/biodiesel/article_alge.html - 62k - |
Harmful Algae : Red Tide
Info on toxic algal blooms. Algae species, photos, adverse impacts and human illness. US distribution maps of hazardous algal blooms (HAB). www.whoi.edu/redtide/ - 14k - |
The Algae Programming Language
a high-level interpreted language for numerical analysis. algae.sourceforge.net/ - 3k - |
Algae: Protists with Chloroplasts
The algae are a polyphyletic and paraphyletic group of organisms. They are defined in differing ways, but are usually considered to be the photosynthetic ... www.tolweb.org/notes/?note_id=52 - 29k - |
News results for algae
Toxic algae closes lake to swimmers -
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Tuesday, February 12, 2008
pteridology
The pteridophytes are vascular plants (plants with xylem and phloem) that neither flower nor produce seeds. Instead, they reproduce and disperse only via spores.
Pteridophyte classification
The pteridophytes do not form a monophyletic group but consist of several groups, the Lycopodiophyta (club mosses, spike mosses, and quillworts), the Equisetophyta (horsetails), the Psilotophyta (whisk ferns), the Ophioglossophyta (adder's tongues and grape ferns), and the Pteridophyta (true ferns).
In addition to these living groups of pteridophytes are several groups now extinct and known only from fossils. These groups include the Rhyniophyta, Zosterophyllophyta, Trimerophytophyta, and the progymnosperms.
Modern studies of the land plants agree that all the pteridophytes share a single common ancestor. However, they are not a clade (monophyletic group) because the seed plants are also descended from within this group -- probably close relatives of the progymnosperms.
Pteridophyte sexuality
These plants are generally sporophyte-oriented; that is, the normal plant is the diploid sporophyte, with the only haploid structure being the gametophyte (prothallium) in season. This basic pattern is like that found in the seed plants but with an important exception. Unlike the seed plants, the pteridophytes have a gametophyte stage that is free-living. As a result, pteridophyte sexuality is more complicated than that of the seed plants. There are several basic categories of sexuality in pteridophytes. The terms distinguish between types of gametophyte sexuality:
- Dioicous pteridophytes produce only antheridia (male organs) or archegonia (female organ) on a single gametophyte body.
- Monoicous pteridophytes produce both antheridia and archegonia on the same gametophyte body.
- Protandrous pteridophytes produce the male antheridia first, and then their female argchegonia.
- Protogynous pteridophytes produce the archegonia first, followed by the antheridia.
Notice that these terms are not the same as monoecious and dioecious, which refer to whether or not a sporophyte plant bears one or both kinds of gametophyte. Those terms apply only to seed plants.
See also
- Embryophyte
- Lycopodiophyta
- Equisetophyta
- Psilotophyta
- Ophioglossophyta
- Pteridophyta
- Plant sexuality
- Fern
References
- Gifford, Ernest M. & Foster, Adriance S. (1988). Morphology and Evolution of Vascular Plants, (3rd ed.). New York: W. H. Freeman and Company. ISBN 0-7167-1946-0.
- Raven, Peter H., Evert, Ray F., & Eichhorn, Susan E. (2005). Biology of Plants (7th ed.). New York: W. H. Freeman and Company. ISBN 0-7167-1007-2.
This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)