General Interest

Armadillos Birth Genetically Identical Quadruplets

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From a Wikipedia research spiral:

Armadillos possess the unique reproductive trait of monozygotic polyembryony, meaning their offspring are genetically identical due to the division of a single fertilized egg into four matching embryos. This development of identical quadruplets has been utilized as a tool for genetic research. It is possible that the monozygotic polyembryony was an adaptation to accommodate for the female’s inability to carry more than one egg during this pre-implantation stage. Delaying the implantation further has no effect on the number of offspring produced.

Armadillos are also carriers of leprosy, as I learned in my Infectious Diseases course in undergrad.  And they have the now unfortunate fear response of jumping, which means they often kill themselves on car bumpers when the vehicle would have otherwise safely passed over the animal.  They are a fascinating creature.

Studies Confirm Nature Is Soothing

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Research coming out of Stanford University's Emmett Interdisciplinary Program in Environment and Resources is unsurprisingly showing that:

A walk in the park may soothe the mind and, in the process, change the workings of our brains in ways that improve our mental health, according to an interesting new study of the physical effects on the brain of visiting nature.

Oranges Are Hybridized Fruits

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Many people think of oranges as a primary, pure, primitive fruit.  In fact, they're a hybrid of pomelos and mandarins!  From "The draft genome of sweet orange (Citrus sinensis)":

"The remarkably high degree of heterozygosity in the genome of cultivar Valencia sweet orange (C. sinensis cv. Valencia), as evidenced in our genomic and cytological analyses, hinted that sweet orange is an interspecific hybrid between pummelo and mandarin. On the basis of the collective evidence, we reconstructed the scenario regarding the ancient primary events of the origin of sweet orange: female pummelo crossed with male mandarin to create the initial interspecific hybrid that was further crossed again with male mandarin to produce sweet orange. This event might have happened at least 2,300 years ago, or much earlier, as sweet orange was recorded in Chinese literature as long ago as 314 BC (3, 38). Although additional genetic changes might have occurred afterward, it is still remarkable that this ancient hybrid genotype seems to be preserved in today's sweet orange, probably because of its strict nature of asexual reproduction (apomixis through nucellar embryo) and manmade selection and propagation by grafting. This scenario explains why most of today's sweet orange cultivars are genetically one biotype and highly heterozygous, with diversification occurring mostly through somatic mutations (7, 39, 40)."

Swiss Cheese Holes Caused By Hay Dust

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Have you noticed fewer holes in your Swiss cheese over the years?  Apparently this cheese (also known as Emmental cheese overseas - something I accidentally discovered for myself on residency in Iceland) had a lot of holes because small particles of hay dust used to regularly drift their way into the milk in the normal course of farming.  Our increasingly industrialized processes sterilized the cheesemaking environment so much that the holes have been mysteriously disappearing.  Now that the cause has been discovered, though, cheesemakers can judiciously add hay dust back into the milk.

Aphids Are Born Pregnant (Unless They're Not Born At All...)

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Did you know that most aphids are born pregnant?  I was thinking about this odd fact since my sempervivum collection (colloquially known as Hen and Chicks) had an aphid infestation due in part to the unusually wet late spring here in Kansas.  Luckily, neem oil has so far discouraged the little ladies from successfully hatching their next two generations.  Below is a close-up of one the several sempervivum species I'm keeping in a rail planter on my porch.


First Fully Warm-Blooded Fish Identified!

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This is cool:

"The opah, or moonfish, is the first known fully warm-blooded fish, according to a study published in the journal Science.
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Certain other fish, such as some sharks and tuna, have what’s known as 'regional endothermy,' or limited warm-bloodedness. It allows them to stay active in colder depths, as well as shallower waters. But the fully warm-blooded opah are unlike all other fish, at least so far as we know it."