Lonely flatworms inject sperm into their own heads

Consider the lengths that some hermaphroditic flatworms will go to in the name of reproduction. In the absence of mating opportunities, hermaphroditic flatworms such as Macrostomum hystrix self-fertilize by stabbing themselves in the head with their penile appendage and injecting sperm, report biologists from the University of Basel in Switzerland today in the Proceedings of the Royal Society B. 

The researchers suspect that the head penetration is necessary simply because the worms can’t fold tightly enough to get their penile appendage any closer to the ovaries. The sperm then presumably swim through the body cavity to the ovaries where development of a hatchling can begin.

Lukas Schaärer/Flickr/Creative Commons

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Crow Rides On The Back Of An Eagle In Once-In-A-Lifetime Photos 

“Crows are known for aggressively harassing other raptors that are much bigger in size when spotted in their territories and usually these ‘intruders’ simply retreat without much fuss. However, in this frame the crow did not seem to harass the bald eagle at such close proximity and neither did the bald eagle seem to mind the crow’s presence invading its personal space. What made it even more bizarre was that the crow even made a brief stop on the back of the eagle as if it was taking a free scenic ride and the eagle simply obliged.”

Photos by Phoo Chan

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Reeves´s muntjac (Muntiacus reevesi)

Reeves’s muntjac is a muntjac species found widely in southeastern China and in Taiwan. It feeds on herbs, blossoms, succulent shoots, grasses and nuts, and was also reported to eat trees. This muntjac grows to 0.5 metres high at the shoulder and 0.95 m in length. The male has short antlers and uses them to push enemies off balance so he can wound them with his upper two inch canine teeth. Reeves’s muntjac is also called the barking deer, known for its distinctive bark, though this name is also used for the other species of muntjacs.

photo credits: Olga Benešová, Margoz, Bardrock, bongowwf

Calcium uptake by mitochondria makes heart beat harder in fight-or-flight response

In a life-threatening situation, the heart beats faster and harder, invigorated by the fight-or-flight response, which instantaneously prepares a person to react or run. Now, a new study by researchers at Temple University School of Medicine (TUSM) shows that the uptick in heart muscle contractility that occurs under acute stress is driven by a flood of calcium into mitochondria–the cells’ energy-producing powerhouses.

Researchers have long known that calcium enters mitochondria in heart muscle cells, but the physiological role of that process was unclear. “The function of mitochondrial calcium uptake during stress generally was linked to the collapse of energy production and cell death,” explained John W. Elrod, PhD, Assistant Professor of Pharmacology and at the Center for Translational Medicine at TUSM, and senior investigator on the new study, which appears June 25 in the journal Cell Reports.

“We show, however, that in periods of acute stress, increased calcium uptake by mitochondria in the heart functions in ways that are good and bad: during the fight-or-flight response, it provides the necessary energetic support for the heart, but during a heart attack, it leads to the death of large numbers of heart cells,” Dr. Elrod said.

Timothy S. Luongo et al. The Mitochondrial Calcium Uniporter Matches Energetic Supply with Cardiac Workload during Stress and Modulates Permeability Transition. Cell Reports, June 2015 DOI: 10.1016/j.celrep.2015.06.017

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Walking on two legs, or “bipedalism,” is a key characteristic defining humans and our early ancestors. But what an odd way to walk and run! 

Join Museum Curator Brian Richmond and Boston University anthropologist Jeremy DeSilva in exploring the great advantages of walking on two legs, as well as the unfortunate consequences of evolving bipedalism from a body plan designed to walk on four, not two, legs. 

Download the podcast of this talk

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Just a few of the beautiful millipedes I found on my North Carolina trip. The first photo is the couple dozen we found just outside our dorm at the station. The proceeding photos are: two color morphs of Cherokia georgiana, the first being my favorite, which I dubbed “the sunset millipede”; Boraria deturkiana; and Boraria stricta.

I have all the photos from that trip ready, so you can expect more to be posted in the coming weeks.

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Ivy-Leaved Toadflax (Cymbalaria muralis)

In English, this plant is also called Kenilworth ivy, coliseum ivy, Oxford ivy, mother of thousands, pennywort, and wandering sailor. In Danish, it’s ‘Vedbend-Torskemund’ (roughly: ‘cod mouth at-the-bend,’ referring to the shape of the flowers and the growth habit). In German: ‘Zimbelkraut‘ (’cymbal herb’); in French: ‘Ruine-de-Rome’ (ruins of Rome).

It’s a sprawling Mediterranean native that has been naturalised throughout Europe, and introduced as an invasive elsewhere. This is in part due to the fact that it colonises and area rapidly, and exhibits uniquely-adaptive tropisms:

This plant has an unusual method of propagation. The flower stalk is initially positively phototropic and moves towards the light – after fertilisation, it becomes negatively phototropic and moves away from the light. This results in seed being pushed into dark crevices of rock walls, where it is more likely to germinate and where it prefers to grow. [x]

I propagated cuttings from a small patch of this plant growing up the side of the house: as with thyme, I’ve planted it on the borders and soil surface of many beds, because it is attractive and nourishing to pollinators, and forms a dense mat of foliage.

The bumblebees that favour this plant don’t even have to fly between blossoms: instead, they crawl around on the stems. I imagine this saves them quite a bit of energy during their foraging.

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Hormones and Gender Transition

With Caitlyn Jenner’s recent transition in the news, more attention is being paid to the transgender community. A big part of gender transition is hormone replacement therapy (HRT). This week, Reactions talks about the chemistry of HRT and what happens when the body undergoes major shifts in estrogen and testosterone — two very powerful hormones.

By: ACS Reactions.

Large predators can be friend too

Recently, arabian researcher has report the encounters of false killer whale (P. crassidens) associated with silky sharks (Carcharhinus falciformis) at different reef sites of the Farasan Banks, Red Sea, Saudi Arabia in 2014.

Despite shark-cetacean aggregations and associations of false killer whales with other cetacean have been reported previously, this is the first description of non-aggressive association of false killer with sharks !!!

The possible benefits of associations between false killer whales and silky sharks remain unclear and the aggregations might be random without direct benefits for the different species. However, shared feeding grounds might provide an explanation for the presence of multi-species groups.  Even though no feeding was directly observed by scientists, prey indicates a previous hunting event and may suggest the possibility of a foraging association

The Drunkest Eye: Do Those Baby Blues Mean Higher Rates of Problem Drinking?

Blue eyes could be a risk factor for alcohol dependence, according to a new Univ. of Vermont study.

People with lighter-colored eyes had a higher incidence of problem drinking, according to the results, published in the American Journal of Medical Genetics Part B.

The 1,263 European-Americans showed a “statistically significant” relation between the blue eye color genes and alcohol-dependence genes, according to the study.

Read more: http://www.laboratoryequipment.com/news/2015/07/drunkest-eye-do-those-baby-blues-mean-higher-rates-problem-drinking

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SYMBIOSIS - Episode 3: Inside The Pea Aphid

Go deep – really deep! – and find out how the pea aphid’s remarkable partnership with Buchnera bacteria works at the molecular level!

By: Day’s Edge Productions.