Indian Paintbrush – A Pretty Parasite

•July 27, 2011 • 10 Comments

Castilleja miniata, a very common paintbrush species in Western North America

Anyone who has spent much time in the Western U.S. is probably familiar with one of our most attractive wildflowers – Castilleja, or Indian paint brush. Blooming riotously in the summer, from deserts to alpine meadows, the nearly 200 species in this genus (many endemic to North America) put on quite a display – a riot of reds, oranges, yellows, pinks, and purples. Despite being maniacally difficult to tell some of the species apart, Indian paintbrush is one of my personal favorite wildflowers, and not just for it’s breathtaking colors.

There are a couple interesting things about Castilleja. First off, the colorful blooms that make it so remarkable are not actually the flowers. They are the leafy bracts surrounding the very inconspicuous and uninteresting greenish white flowers at the very tip. Much like poinsettia, all the action is in the specially formed leaves. You can kind of see this once you know what to look for, as the color sort of shades back to green as you move down the stem.

Haustorium. Note how it goes through the tissue but doesn't puncture the cells.

Another thing you may or may not notice about Castilleja is that you almost never see it alone. Some wildflowers like mountain bluebells or little sunflower form huge monolithic stands, but Indian paintbrush is almost always scattered through an area with other plants. The reason for this is that, although it looks just like any other green forb to the naked eye, Castilleja is actually parasitic on other plants. In fact, it comes from an entire family of plant-on-plant parasites, Orobanchaceae. Although levels of parasitism range greatly in this family, they all have a defining characteristic: haustoria. Haustoria are specialized roots that drill into the roots of other plants for the purpose of stealing their resources.

Of the parasitic plants found in this family, Castilleja is actually a fairly mild parasite, known as a root hemiparasite. Since they have fairly normal green foliage, they can photosynthesize on their own. But they get a huge boost in fitness from stealing water and other essential minerals from a host plant. This may be an adaptation to places where resources, like water, are limited, the growing season is short, or the soil is poor.  And while in the wild Castilleja is almost never found without a host, they can technically survive on their own, although they are much less robust in every way if grown in isolation. Castilleja also does not kill its host plant, although it often does take a toll on its fitness and growth.

Castilleja species are generalist parasites. Although certain species do much better with and seem to “prefer” particular host species, they will usually take whatever they can get. Because the species available to them may vary greatly and because they inhabit such a wide range of ecosystems, it’s to their benefit to be flexible and work with what is around – if you’re too picky you might find yourself with no host at all. In dry areas, sagebrush is a common host plant to desert species of paintbrush. In other places, lupine species (another large genus of the western U.S.  found in a range of habitats) are one of the most common hosts. In fact, Castilleja plants that are able to latch on to lupine as a host plant may be very  lucky individuals.

Red paintbrush grooving on lupine; a common sight in the summer.

As a member of the bean family, lupines have a symbiotic relationship with nitrogen-fixing bacteria and any plant parasitizing them is going to get increased access to nitrogen. Studies have shown that Castilleja using lupines as host experience better growth, increased reproduction, and increased pollen output. Lupines may even offer some protection from herbivory to Castilleja, as along with nutrients parasites also receive the alkaloid lupinine, which is toxic and bitter to animals. This protection may be conferred to the Castilleja, although studies have shown mixed results in whether having lupine as a host actually does decrease herbivory on Indian paintbrush or not. Either way, it’s clear there are big benefits to taking advantage of lupine, and in my area it’s not uncommon to see meadows full of almost exclusively lupine and paintbrush.

Castilleja, along with other root hemiparasites, can actually have a surprisingly large effect on community structure as a whole. Introduction of a species like this can shift the entire dynamic by helping or hurting various other competitors for resources. Say you have a plant community that is dominated by one species of herbaceous plant. There is another species present, but it just can’t compete and is barely hanging on. Now, in comes a root hemiparasite like Castilleja. It gets big benefits from parasitizing the dominant species and not much from the secondary species. But in the process of parasitizing the dominant species it greatly reduces that species’ fitness. Suddenly, the secondary species can compete! This can lead to a community going from a virtual monoculture to either a stable system with the three species (parasite, dominant, and secondary) existing in roughly equal proportions, or a constantly fluctuating system where one species becomes extremely successful for awhile before the other takes over in a repeated fight for dominance.

Castilleja rehexifolia, a pretty pink paintbrush

In addition, if the root hemiparasite does better on the less dominant species, it may actual confer a competitive advantage on the secondary species and help it to increase its range against the dominant species. While the secondary species alone may have no hope of out-competing the dominant species for limited resources, in combination with Castilleja or another hemiparasite they together may succeed in elbowing out the normally successful dominant and either sharing or completely excluding it from the system it previously ruled.

As you can see, Castilleja and other root hemiparasites are forces to be reckoned with. But there is still much we don’t know about them. Are there other ways they confer benefits to their hosts? Are some species evolving to be host-specific? How much do they actually take from their hosts? And is their color (variable within a species and location) dependent on the nutrients and minerals they receive from the host plant or is there another factor? The complicated systems in which they exist and the huge variation among species make any questions about this genus difficult to answer definitively.

References:

Smith, D. (2000). The Population Dynamics and Community Ecology of Root Hemiparasitic Plants. The American naturalist, 155(1), 13-23. doi: 10.1086/303294.

Adler, L. S. (2003). Host Species Affects Herbivory, Pollination, and Reproduction in Experiments With Parasitic Castilleja. Ecology, 84(8), 2083-2091. doi: 10.1890/02-0542.

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Lazy Friday Links 7.1.11

•July 1, 2011 • Leave a Comment

What, July already? Happy Canada Day everyone! And happy Independence Day on Monday! I hope everyone’s got fun plans for the weekend. Since it’s supposed to hit 103 F here on Sunday, mine include “finding a cold lake above 10,000 ft and staying there”. Enjoy the linkfest as you run out the clock before the holiday weekend.

Ecology/Evolution Links:

1: This is what we get for decades of fire suppression. The mega-fires now raging in the southwestern U.S. are so large and intense they may cause permanent damage to the ecosystem, despite it normally being considered a fire-adapted system. Small fires rejuvenate, but ones like these only devastate  (Wired Science).

2: Crows, already one of the animals strongly in the running to take over the planet from us (along with octopi, dolphins, and ants), not only have great memories but they can transfer their knowledge of danger to other crows who haven’t experienced them. Bird telepathy? Let’s hope not, but however they do it, it’s wicked cool (Global Animal).

3: Let’s hear it for the owls! The National Fish and Wildlife Service this week, after years of waiting, finally published recovery plans for both the Northern Spotted Owl and the Mexican Spotted Owl. That is, if the Mexican Spotted Owl can survive in the smoldering wreckage that is now much of its territory (NY Times).

4: Sing me home! A detailed explanation of population structure and fluctuations of  southern right whales over the past few centuries. No one knows for sure how many there are now, but the good news is they seem to be doing fairly well (Deep Blue Home).

5: Scientists are putting together an advertising campaign aimed at monkeys. No, it’s not to get them to volunteer for lab experiments. Having taught them to use money, they now hope associating a product with sex (female monkeybits) and dominance (alpha males) will make them chose that product over others. My question is, will female and male monkeys be equally susceptible to the same ads? (io9)

General Science Links:

1: More casualties of on-going budget crises – public health. Due to a government shutdown, Minnesota will lose many services, including it’s incredible public health unit which does a Swedish-quality job of stopping foodborne illnesses before they spread. Because people getting sick from MN food products will help the economy… (Superbug).

2: Remember kids, there’s no such thing as “chemical-free”. Period. If you are chemical-free, see your doctor as you may have become a ghost (Speakeasy Science).

3: As a culture and as a species we are obsessed with things we can’t explain, often lumped together under the banner of the “paranormal”. But why? Do our brains hold an answer? Salon presents an interesting and vaguely science-y discussion (Salon).

4: Autism, ever more common in this country, is often spoken of synonymously with an inability to empathize. But is that really true, or are are we confusing an inability to understand signals with a lack of feeling? (Thinking Autism Guide)

5: Matter is so awesome! Japanese researchers have developed a new alloy that can return to its original shape at a very wide range of temperatures. Apparently we already had ones that could do at a narrower range. Kinda puts some of those Roswell reports in perspective (PhysOrg).

Because-I-Feel-Like-It Links:

1: A statistical exercise of dubious value/accuracy but limitless fun calculates the number of things you are more likely to do than intentionally click on a banner ad. Better not tell that to the advertiser, though, or our whole internet economy could come crashing down (The Atlantic).

2: Misdirection – sometimes it’s the only way (xkcd).

3: Stephen Colbert makes mockery of campaign finance laws even more realer by forming his own Super PAC ostensibly to use Viacom money to run campaign ads in this election. Funny joke or brilliantly sneaky political plot? I guess we’re find out in 2012 (AV Club).

4: Dan Savage and others make a case for (some) non-monogamy. Can’t say I totally agree with him, but I can’t really judge other peoples relationships, and its a fascinating article nonetheless. Plus I adore the guy (NY Times).

5: An Anabaptist makes a compelling case for not celebrating Independence Day if you’re a Christian or a pacifist. Or both. Uncomfortably thought provoking (Pangea Blog).

And a new section wherein I tell you what to do with your weekend:

Make: An easy and impressive no-bake raspberry cheesecake. Follow this recipe, but use chocolate wafers for the crust instead of regular grahams, then top with fresh raspberries. Or a mix of raspberries and blueberries for a patriotic theme. Great to bring to cookouts this weekend.

Drink: Polygamy Porter, a Utah favorite. With a smooth taste and the tagline “Why have just one?”, it’s hard to resist. If you can’t buy it in your area, you can probably order it online (depending on your state) or pester your local store to stock it. Got wives? Get beer.

View: The night sky holds a lot of excitement in July. Mercury will be the first planet out, but we should also be able to see Venus, Saturn, and Titan with the naked eye.

See: Nothing! No good movies are coming out this weekend unless you’re in the vicinity of a showing of the limited release comedy “Terri“. If not and if you’ve already seen the brilliant Super 8, then go read Slate’s review of Transformers 3, realize you’ve dodged a bullet, and then rent the extremely underrated and frighteningly  fitting cult comedy Idiocracy and reflect upon how the former relates to the latter…

Go: Somewhere cool! It’s gonna be varying degrees of scorching across the country this weekend, and all the major lakeshores and beaches are likely to be packed. I recommend backpacking Utah’s Highline Trail, which only just finished melting out after an insane amount of snowfall this winter. Rolling terrain keeps you at a cool 10,500-13,000 feet with plenty of coyotes and mountain goats for company.

Book Review: A Rum Affair

•June 30, 2011 • 1 Comment

Sorry for the long absence, folks! I caught a hideous summer cold which totally took me out for about ten days and then I was away for a bit. Summer colds seem so unfair – in the winter if I’m sick I’ll just lean into it. It’s cold outside, there’s not much to do other than work and I just dose myself with nyquil and sleep it off, watch trashy TV, and order takeout. In the summer it’s already hot and sticky and there are so many fun and interesting things to be doing – I resent every second spent in forced convalescence.

Anyways, on to our selection today. Whether you will enjoy “A Rum Affair: A True Story of Botanical Fraud” by Karl Sabbaugh probably depends greatly on how much of a plant or history nerd you are. In brief, the book is essentially a journalistic investigation of an incident in England in the early/mid 1900’s in which a distinguished professor of botany, John Heslop Harrison, was accused by John Raven (an amateur, but respected, plant enthusiast) of sowing rare species of sedges and other plants on the Scottish Island of Rum and then claiming to have found them growing there naturally, for the purposes of supporting his pet theory regarding the timing and extent of the last glaciation. Because Harrison was so respected and there was no way to prove the accusations, the papers regarding it were sealed and hidden away in the dusty records of Newcastle, nearly forgotten.

The author investigates the accusations, as well as all the incidents surrounding them and the lives and careers of the two major players, the professor and the accuser.  Although it is clear from the get-go (and the title itself, really) that the author believes the accusations of fraud to be true, he makes a fairly convincing and rational case for the guilt of the professor  (at least to this reader), without completely dismissing the value of Harrison’s other work and contributions to botany and natural history.

Although the book is highly historical in nature and Sabbaugh is not a botanist, the plants and the field of botany at the time get a very good going over, with detailed explanations of the fraud and the species involved. His lack of expertise is an asset here, as he does not shoot over the lay reader’s head with technical jargon but labors to explain the case and the science as it was explained to him. He also frames some of the conflict as a class struggle between the profession of humble origins and the privileged, talented amateur, which sheds a different light on the accusations and garners sympathy for the seemingly-insecure Harrison (although Raven is generally the more likable character). At times the writing is a bit dry and repetitive, but it is liberally sprinkled with wry humor and engaging anecdotes of those he is writing about and of his own experiences during the research process.

Although the basic information of the case is summed up nearly from page 1, if you are interested in the more esoteric details I feel the rest of the book is worth a read. This is a case that will never truly be solved; the evidence against Harrison is damning but by no means conclusive. But reading about it in detail not only provides an interesting glimpse into the world of British botany in the time period surrounding the second World War, but it also provides a setting for a discussion of larger issues regarding scientific ethics, verifiability, class discrimination, and the seeming immunity from accountability of respected authority figures in the scientific community.

I recommend this book to plant nerds, 20th century history buffs, and those looking for a good, factual mystery. It’s not terribly long and reasonably enjoyable despite some slow bits. But remember to read with a skeptical eye and judge the facts for yourself.

Onychomys: Tiny Terror of the Western Deserts

•June 14, 2011 • 3 Comments

Here’s a riddle for you: What stalks its prey like a cat, howls like a wolf, and weighs about one ounce?

Give up? The grasshopper mouse! Onychomys is a genus of small mice native to western North America. The three species, O. leucogaster, O. torridus, and O. arenicola, have overlapping ranges with O. arenicola (Chihuahuan grasshopper mouse) stretching down into Mexico, while O. leucogaster‘s range reaches up to southewestern Canada. They are desert and arid adapted rodents, able to survive harsh conditions very well and are mostly found in desert, scrub, and dry plains in their ranges. Their characteristics and behavior are all very similar so I’m going to talk about the genus as a whole, although there are minor differences between species in terms of diet, habitat, etc.

Onychomys mice are very small, usually just a little over an ounce. They are actually quite adorable, with darkish brown to gray fur on their backs and light to white fur on their undersides, and a short, thick tail less than half the length of their bodies. They have relatively small ears and, although not bipedal, rise up on their hind legs and use their front limbs for various tasks rather regularly. If you were to see one in the wild, you would just think, “hey, a mouse with a short tail!”.

What makes Onychomys special – and fiercesome -among the hordes of North America rodents is its carnivory. Actually, carnivory itself is not that unusual among rodents, particularly desert ones. While many species are adapted to specialize in seeds or plant material, most are more omnivorous, incorporating small arthropods and sometimes even carrion into their diets. It’s the level of carnivory of these little guys that is impressive. They eat almost exclusively meat – mostly insects but also scorpions, small snakes and lizards, and even other rodents!

Now, these are not animals they have found dead and consumed. Onychomys are hunters. Quite aggressive ones. They will pretty much go after anything about their size or smaller that moves (with a very few exceptions in species which have toxins that make them inedible which the mice can smell from a distance), and will attack unrelentingly until it is dead. When they are near prey they sniff to identify it and then track its scent trail, silently stalking it until they are close. Then they attack, lunging at the prey with open mouths and front paws, trying to subdue it with a killing bite. In the case of vertebrates, they often go for the back of the neck, severing the spinal cord with their teeth. With arthropods they often first try to disable whatever defense the animal has, removing the stinging tails of scorpions, for instance.

From Langley, 1986

They almost never give up on prey once they’ve decided to attack, although sometimes after it is dead they may decide it’s not edible and leave it. Onychomys are of the “kill first, ask questions later” school of predation it would seem. Scientists who have studied them are often astounded at their level of aggression and their heedlessness of danger, as they attack everything from harmless crickets to other mice to the most poisonous species of scorpions in North American with the same vigor. They’ve even been known to kill kangaroo rats and cotton rats much, much larger than them in the lab (although it’s unlikely they hunt those species in the wild). In the eastern part of their range, they hunt small prairie birds.

It takes them a bit longer to subdue something heavily armed like a scorpion, but they usually manage it. Part of the reason they are able to do this is that Onychomys species seem to be at least partially immune to neurotoxins. The scorpions will sting them during an attack, and while they may retreat briefly and seem to experience pain from the wound, the normal effects of paralysis didn’t set in and the mice will return to their attacks. In the lab, trials have been done giving the mice various drugs, including sedatives and anti-psychotics, to see if that will decrease their aggression towards prey or each other.

They don’t. Drugs that would lay you or I out flat seem to roll off the backs of Onychomys and they just keep on going. They are born fighters – fairly young mice raised exclusively in a lab setting are still efficient killers when presented with prey for the first time, even when compared with wild-caught mice.

So why are these mice so aggressive and carnivorous? It seems to be a desert adaptation. Water is a problem for everyone in the desert, particularly mammals. Many rodents have developed similar adaptations to conserve/obtain water. These are often a combination of be behavioral (only coming out at night, eating only the moist parts of plants) and physiological (kidneys that concentrate urine to prevent water loss, the ability to extract metabolic water even from fairly dry food sources). While Onychomys can concentrate their urine somewhat, they are not as efficient at it as many other desert species and they can’t get metabolic water from seeds like kangaroo rats (many of which never need to drink or even eat particularly succulent foods).

It's like something from Dune: "His water is mine, now!"

They get their water from meat. Animals have a lot of water in them, more than many desert plants. Onychomys essentially usurp the water carefully hoarded by other species in their own bodies for their survival. Trials have been done feeding these rodents exclusively on meat (other mice, beef, and liver) and they were able to live quite happily without drinking water for months. If the meat was cooked, reducing the water content, they lost weight and their health immediately went downhill. It takes a lot meat to supply an active mouse with all the water and calories it need to survive in the desert, and it takes a lot of aggression to produce the high number of kills necessary to maintain that supply.

Although Onychomys are rodents, they eat like carnivores and thus sort of act like them too. They live alone or in pairs with young, not unusual for mice, but they maintain particularly huge home ranges, up to nearly 8 acres for some males. Which is simply gigantic if you’re talking about a mouse the size of a salt shaker! They are nocturnal and maintain extensive burrows in their territory which they use to live in, to escape from other predators, and to store food in the winter. They patrol and defend their territories viciously, eagerly fighting, killing, and eating intruders of the same species and other rodent species. Females have even been known to kill and eat their mates.

And they are vocal. They make various calls of alarm and identification, including the infamous howl. When patrolling their territory, they will often rise up on their hind limbs, throw back their heads, and make a loud piercing, cry. They do this, of course, particularly on spring spring and summer nights when the moon is full, although it is unknown if this behavior is a mating call or primarily a territorial display. This has led to another common name for Onychomys – wolf mouse.

 

References:

Rowe, A., & Rowe, M. (2006). Risk assessment by grasshopper mice (Onychomys spp.) feeding on neurotoxic prey (Centruroides spp.). Animal Behaviour, 71(3), 725-734. doi: 10.1016/j.anbehav.2005.08.003.

Ruffer, D. G. (1966). Observations on the calls of the grasshopper mouse (Onychomys leucogaster). The Ohio Journal of Science, 66(2), 219-220.

Timberlake, W., & Washburne, D. L. (1989). Feeding ecology and laboratory predatory behavior toward live and artificial moving prey in seven rodent species. Learning, 17(1), 2-11.

Langley, W. M. (1986). Development of predatory behavior in the southern grasshopper mouse (Onychomys torridus). Behaviour, 99(3/4).

McCarty, R. (1975). Onychomys torridus. Mammalian Species, 59, 1-5

McCarty, R. (1978). Onychomys leucogaster. Mammalian Species, 87, 1-6

Additional information from Animal Diversity Web and “A Desert Calling” by Michael Mares

Book Review: “A Desert Calling”

•June 13, 2011 • 1 Comment

When I picked up “A Desert Calling” by Michael A. Mares from the SLC library (my new favorite place – six floors of books and a coffee shop!) I had next to no idea what to expect from it. Since I recently moved to a state that’s more desert than not, I thought learning more about the ecology of deserts would be a nice place to start. Bu when I grabbed it I really didn’t know whether this book was a hard-hitting ecological text or a spiritual mediation on the desert landscape. In fact, I rather suspected the latter, given the title.

I was pleasantly surprised to find that the book is instead part scientific memoir of 30+ years of field work on the small mammals of the world’s deserts, and part non-technical exploration of the greater principles of ecology and scientific study as they related to arid climates. The two components are woven together fairly skillfully to create a narrative that is both personal and overarching, and includes many fascinating case studies of individual species and associations that any nature geek will eat up with a spoon. From kangaroo rats that can go without free water their entire lives to pink fairy armadillos that swim through sand dunes, around every corner is another fascinating desert mammal (usually a rodent), that you probably have never heard of before.

On the personal front he talks unflinchingly about the challenges of field work in a wry, understated style. These adventures include a brush with death at the hands of a bat-borne virus, tents being shredded by the wind, getting nearly hopelessly lost in massive thorn forests, and the time their field site was declared an open shooting range during an Argentine war (“It made continuing to work there difficult,” he tells us). He also explains in detail the process and necessity of collecting rodent and mammal specimens for further study in museum collections.

Digression: Although I understand that we could not properly identify, describe, and study animals without comprehensive museum  collections, study skins, and the data gleaned from dissections, I have to admit that personally I am rather squeamish about that part of field biology. I fully admit that this bias extends mainly to vertebrates and I will happily collect a bug any day of the week, and that this is probably hypocritical. I just have a hard time reconciling the fact that the first thing ecologists usually do when we discover a new or rare animal is kill it with our overall conservatory efforts. Although the author is correct when he points that there’s never just one rodent, I also find the argument that it would have died anyway rather a flimsy one. Basically,  I know collections and type specimens are vital to science, but have personal misgivings which may or may not be valid. Although since many of the collected specimens the author mentions seem not to have just gone to a museum as skins but also into his stewpot as dinner when he had no money to buy food I can hardly begrudge him. Back to your regularly scheduled book review.

The author also talked about the less obvious problems with field work such as money, politics, and internal strife in the countries one wants to work in. He is equally candid about the scientific process and his personal experiences of bringing biases to his work and learning to overcome them. He is honest about being wrong, and what happens when scientists make assumptions about things that haven’t been properly studied. In the 70’s, when he was doing much of his field work, there was an overwhelming tendency in ecology to assume that similar habitats should contain nearly identical community structure and populations, and that these models could be applied around the world (models usually based only on North American ecology). He explains over the course of the book what parts of these ideas were correct and which were not – and how he discovered the difference. Along the way he includes narrow escapes from death, tales of how he and his crew discovered several new mammal genera, a hymn of praise to taxonomists, and a plea for desert conservation around the world.

In terms of science, his main focus is convergent evolution. He uses individual case studies to show how animals in different deserts solve the same problems in similar (or in some cases, radically different) ways despite being only distantly related. The takeaway lesson is that while you can’t expect similar habitats to always produce identical creatures, there are a limited number ways of solving the problems create by living in an area without much water, and we see these repeated again and again in nature – although sometimes with novel twists.

The explanations of the adaptations and broader ecological principles are easy to understand for a lay person, but not dumbed down at all to those who already have a basic foundation in ecology. He includes all scientific names but does not insist on referring to them only by their scientific nomenclature, and is diligent about going back and reminding the reader of pertinent facts instead of just assuming they completely absorbed a new concept from a brief mention earlier in the book. Overall, it was an easy and engaging book to read, and while long enough to provide an in-depth look at many topics, was not so long that it began to drag before the end. I highly recommend this to anyone even vaguely interested in deserts or small mammals – although be warned, if you want to learn about birds, lizards, or plants, look elsewhere. The man writes what he knows.

Sunday Nature Photography Vol #2

•June 12, 2011 • 1 Comment

This gorgeous plant is Echinocereus triglochiatus Englemann, also known as claretcup cactus. No matter how many times I see it, I still find it startling to encounter a cactus in bloom. It seem so rare and magical, even though it’s actually not uncommon for many species. We encountered many blooming cacti on our Memorial Day trip to Arches National Park, mainly prickly pears (Opuntia spp.) in yellow or pink, but we only saw a few of these and they are hands down my favorite for their rich, blood red blooms.

Claretcup cactus is actually not terribly rare, although maybe not as common as prickly pears, which grow simply everywhere. There are a number of varieties which can range from having dense spines like this to no spines at all. The flower shade can differ as well, from wine-colored like these to more orange-y or pinkish. One variety, the Arizona hedgehog cactus is federally listed as endangered, due to it’s extremely limited range.

In general, the claret cup cactus can be found all over the southwestern U.S. and northern Mexico, in Ponderosa pine, Pinyon – Juniper, Sagebrush, Desert or Plains grassland, Desert shrubland, or Southwestern shrubsteppe habitats. It often grow in dense mounds of up to 500 stems (remember, in cacti the “barrel” is the stem and the spines are the leaves), although can also occur as just one or a few stems at a time. The dense mounds may offer some protection from fire or predation to those plants on the inside. They also conserve temperature, keeping the plants cooler throughout the day and then rising in temperature towards the end of the day and keeping them warmer on cold nights.

The beautiful flowers are pollinated mainly by hummingbirds, and the fruit when it ripens is bright red, juicy and sweet. It is edible by humans and most other animals, and is probably a minorly important source of food some desert creatures. Some rodents dig burrows underneath claretcup cactus colonies and nibble at the roots, which can eventually kill the plants.

If you want to see these pretty plants in bloom, head to southern Utah, Colorado, Nevada, Arizona, New Mexico, or California in April through June.

 

 

Lazy Friday Links 6.10.2011

•June 10, 2011 • Leave a Comment

Ecology/Evolution Links:

1: Plant and animal discrimination, you say? A group of 18 ecologist have taken to the pages of Nature to get us to stop hating on invasives. Sorry, I’m just not buying it. Not everything new is bad, but mostly what we’re talking about are virulent life forms redistributed by humans in an untimely fashion – not gradual migrations (Wired).

2: A very cool and unique aquatic air-breathing spider solves its oxygen problem by taking the atmosphere with it. It can effectively use its home-made bubble as a gill to extract oxygen from the water. Post includes nifty video (Not Exactly Rocket Science).

3: Super-scary superbug with enzyme NDM-1, previously discovered in an Indian patient found, is found at a U.S. military hospital in Afghanistan for the first time. Maryn McKenna explains what the big deal is – and why it should probably be a bigger deal (Superbug).

4: More spiders? I just couldn’t help myself. The incredible Dr. Bondar shows us that handindicapped spiders can still weave a good web, even if it is a little different-y. Don’t judge them – they can do missing two legs what I can’t do with all my legs (Carin Bondar).

5: Chimps just want it more. An *ahem* novel way of solving a spacial problem involving a peanut and a…well, just read for yourself (BBC News).

General Science Links:

1: You think things like rain, snow, and hail just happen on their own? Nope. Bacteria control the weather. Okay, not just bacteria but since I’m not sure I had ever thought about atmospheric bacteria before, I’m gonna give them most of the credit (Highly Allonchthonous).

2: What is an ocean gyre? How do they work? And will they pull your ship down to the depths of Davy Jones’ locker? Yar! Ocean gyres explained, with oceanographer Emanuele Di Lorenzo (EarthSky).

3: A succinct and coherent response to incoherent reporting on the Higgs-Boson. This week Deborah Orr from the Guardian confused “physics” and “religion”. And also “journalism”. Here’s a summary with well-deserved smackdown (And Another Thing…).

4: Yes, the lights stayed on this week, but turns out we’ve just been lucky so far. Solar storms of the magnitude of ones that occurred in recorded history could easily knock out a chunk of the electrical grid for years. Yes, YEARS. Start saving your candles and bear fat, people! (Scientific American)

5: A new report sheds some light on the genetic causes of autism (hint: it’s not fromsomething you stick in your kids arm) and why girls have it so much less often than boys. Although this study reveals even more complexity to the condition than previously thought, it may provide hope for treatment using the female brain as a model (Nature News).

Because-I-Feel-Like It Links:

1: What to make for dinner this weekend (a personal favorite): Scallion pancake and cold sesame noodles. Although personally, I prefer my scallion pancake with Thai sweet chili sauce over the soy-based sauce in that recipe.

2: How to mind your own business. Will it make you happier? Probably. Will it make those around you happier? Most definitely (The Happiness Project).

3: Lessons from “127 Hours”:  how the movie should have ended. There’s more to be learned from Danny Boyle’s intense epic than how to cut your arm off with a dull knife or that a GPS with emergency beacon is a good investment (The Oatmeal).

4: We all have friends who are, well, kinda fake. But do you have actual fake friends on Facebook? Well, you and I probably don’t but if we were important, we might! (BlogAds).

5: Rachel Held Evans offers some in-depth advice on freelancing, writing, and making money. A very down-to-earth perspective from someone who is  fairly successful but still struggles with the day to day aspect of paying the bills (Rachel Held Evans).