This tumblr's for all the great men and women of science for whom we owe our current understanding of the natural world; their achievements, their failures, and even their quirks, we celebrate them all.
For Science. For Inquiry. For Humanity.
Human Evolution: Cultural Roots
A South African archaeologist digs into his own past to seek connections between climate change and human development.
Metal scrapes on hard sand as archaeologist Chris Henshilwood shaves away the top layer of sediment in Blombos Cave. After just a few moments, the tip of his trowel unearths the humerus of a pint-sized tortoise that walked the Southern Cape of South Africa many millennia ago. Next come shells from local mussels and snails amid blackened soil and bits of charred wood, all remnants of an ancient feast. It was one of many enjoyed by a distinct group of early humans who visited Blombos Cave over the course of thousands of years.
The Still Bay culture was one of the most advanced Middle Stone Age groups in Africa when it emerged some 78,000 years ago in a startlingly early flourishing of the human mind. Henshilwood’s excavations at Blombos Cave have revealed distinctive tools, including carefully worked stone points that probably served as knives and spear tips, and bits of rock inscribed with apparently symbolic designs. But evidence of the technology disappears abruptly in sediment about 71,000 years old, along with all proof of human habitation in southern Africa. It would be 7,000 years before a new culture appeared, with a markedly different toolkit, including crescent-shaped blades probably used as arrowheads.
Credit: Clinical and Translational Science 2012
On February 2, groundhog weatherman Punxsutawney Phil roused from hibernation to predict six more weeks of winter. Scientists may snicker at people who think they can learn about the arrival of spring from a furry rodent, but researchers aren’t laughing when it comes to learning about human health from animals that check out for the winter.
Understanding how hibernators, including ground squirrels, marmots and bears, survive their long winter’s naps may one day offer solutions for problems such as heart disease, osteoporosis and muscular dystrophy.
Despite appearances, hibernation is not the same as going to sleep for a long time. It is extreme living by any measure. For about half the year, hibernating animals stay in their dens or burrows in a state of suspended animation, waking up every now and again to go to the bathroom. Most hibernators eat or drink nothing, living solely off the fat they built up before winter began.
To make fat stores last, animals lower their metabolism and body temperatures. Black bear body temperatures drop to about 33º Celsius (about 91º Fahrenheit), but the bodies of most small mammal hibernators, such as ground squirrels and woodchucks, plunge to nearly freezing. Some Arctic ground squirrels hold steady at subzero temperatures. For all these animals, heartbeats and breathing nearly cease. These are feats of physiological daring that non-hibernators, including humans, could never survive.
Yet sometimes humans do have to deal with more moderate versions of hibernators’ challenging circumstances — following periods of weight gain, immobilization or blood loss, for example. So, many scientists think some tricks of the hibernation trade might be a boon to human medicine.
Trying to find ways to treat human diseases with the help of animals is nothing new. Researchers often attempt to solve medical riddles by first creating versions of disorders, such as muscular dystrophy or stroke, in mice or other lab animals and then figuring out what goes wrong. But even when researchers know what’s broken, a fix is not always obvious. Hibernators, though, have already found ways to cope with body and lifestyle changes that would lead to disease in humans.
Click title to read more.
Sunflowers are a consistent theme in van Gogh’s body of work, some examples of which are today worth tens of millions of dollars. But the flowers he painted often differ from the common gold blooms we are used to seeing. Was this just impressionist license? A result of his dementia?
University of Georgia researchers think they have tracked his “teddy-bear” blooms to a set of genetic mutations that are common in sunflowers. They weren’t able to cross-breed the green-centered, fluffy varieties of van Gogh’s paintings, but they think that all the mutations to do so are out there in the wild.
Bonus: Today, March 30, is Vincent van Gogh’s birthday! He’d be 162. If he weren’t in space, cloned and held prisoner by NASA, animating ocean currents like they were in ”Starry Night”.
(via Wired Science)
CO2 Transport: Carbaminohemoglobin
Of the CO2 that diffuses from the tissue cells:
- 93% diffuses into red blood cells, 23% of that combines with hemoglobin, while 70% is converted to bicarbonate ions
- 7% dissolves in plasma
- Globin: Protein portion of the hemoglobin molecule
- 23% of CO2 binds to globin to form carbaminohemoglobin
- Carbaminohemoglobin forms in regions of high PCO2
- Formation is reversible
In regions of lower PCO2 (lungs), CO2 dissociates from carbaminohemoglobin
I didn’t know this… yes, maybe I am super naive…
BUT I was curious, and thus, you must read and learn with me.
I’m sure there are a few branches that are not listed.
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Biology, the study of life, has many aspects to it and many specializations within this broad field. Below is an alphabetical list of many of the branches of biology.
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Agriculture - study of producing crops from the land, with an emphasis on practical applications
Anatomy - the study of the animal form, with an emphasis on human bodies
Biochemistry - the study of the chemical reactions required for life to exist and function, usually a focus on the cellular level
Bioengineering - the study of biology through the means of engineering with an emphasis on applied knowledge and especially related to biotechnology.
Bioinformatics - also classified as a branch of information technology (IT) it is the study, collection, and storage of genomic data
Biomathematics or Mathematical Biology - the study of biological processes through mathematics, with an emphasis on modeling.
Biomechanics - often considered a branch of medicine, the study of the mechanics of living beings, with an emphasis on applied use through artificial limbs, etc.
Biophysics - the study of biological processes through physics, by applying the theories and methods traditionally used in the physical sciences
Biotechnology - a new and sometimes controversial branch of biology that studies the manipulation of living matter, including genetic modification
Botany - the study of plants
Cell Biology - the study of the cell as a complete unit, and the molecular and chemical interactions that occur within a living cell.
Conservation Biology - the study of the preservation, protection, or restoration of the natural environment, natural ecosystems, vegetation, and wildlife
Cryobiology - the study of the effects of lower than normally preferred temperatures on living beings.
Developmental Biology - the study of the processes through which an organism develops, from zygote to full structure.
Ecology - the study of the ecosystem as a complete unit, with an emphasis on how species and groups of species interact with other living beings and non-living elements.
Entomology - the study of insects
Environmental Biology - the study of the natural world, as a whole or in a particular area, especially as affected by human activity
Epidemiology - a major component of public health research, it is the study of factors affecting the health and illness of populations
Ethology - the study of animal behavior.
Evolution or Evolutionary Biology - the study of the origin and decent of species over time
Genetics - the study of genes and heredity.
Herpetology - the study of reptiles (and amphibians?)
Histology - The study of cells and tissue, a microscopic branch of anatomy.
Ichthyology - the study of fish
Macrobiology - the study of biology on the level of the macroscopic individual (plant, animal, or other living being) as a complete unit.
Mammology - the study of mammals
Marine Biology - the study of ocean ecosystems, plants, animals, and other living beings.
Medicine - the study of the human body in health and disease, with allopathic medicine focusing on alleviating or curing the body from states of disease
Microbiology - the study of microscopic organisms (microorganisms) and their interactions with other living things
Molecular Biology - the study of biology and biological functions at the molecular level, some cross over with biochemistry
Mycology - the study of fungi
Neurobiology - the study of the nervous system, including anatomy, physiology, even pathology
Oceanography - the study of the ocean, including ocean life, environment, geography, weather, and other aspects influencing the ocean. See Marine Biology
Ornithology - the study of birds
Paleontology - the study of fossils and sometimes geographic evidence of prehistoric life
Pathobiology or pathology - the study of diseases, and the causes, processes, nature, and development of disease
Parisitology - the study of parasites and parasitism
Pharmacology - the study and practical application of preparation, use, and effects of drugs and synthetic medicines.
Physiology - the study of the functioning of living organisms and the organs and parts of living organisms
Phytopathology - the study of plant diseases
Pre-medicine - a college major that covers the general aspects of biology as well as specific classes relevant to the study of medicine
Virology - the study of viruses and some other virus-like agents, usually considered part of microbiology or pathology
Zoology - the study of animals and animal life, including classification, physiology, development, and behavior (See also Entomology, Ethology, Herpetology, Ichthyology, Mammology, Ornithology
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The italics are the branches of biology I will be taking before I can apply for grad school.
COME ON, BIO! SHOW ME WHAT YOU GOT!
Available surface area (varies in different tissues)
Partial pressure gradients
Rate of blood flow varies (metabolic rate of tissue)
Metabolic rate: Body’s rate of energy expenditure; the total heat produced by all the chemical reactions and mechanical work of the body
Internal Respiration: O2 and CO2 Exchange
PO2 entering the systemic capillaries are lower than alveolar PO2
The small decrease is caused by imperfect ventilation-perfusion coupling in the lungs
Gas exchange continues until equilibrium is reached
Mounted specimen from the Krasiejów Museum in Poland.
When: Mid Triassic (~228 - 216 Million Years Ago)
Where: Europe and North America
What: Metoposaurus is an amphibian that lived on the northern continents during the mid Triassic. It was very large compared to modern amphibians, at 10 feet (3 meters) long and weighing an estimated 1000 lbs (450 kg), but these large amphibians were typical of this time, and for tens of millions of years previously. Its limbs are fairy small and weak for its body size, leading researchers to conclude it spend much of its time in the water. Its head was very well adapted for catching fish, with its dozens upon dozens of needle like teeth. Its head was extremely flat, again typical for these amphibians. A flat head like this would have allowed it to breath and look over the surface of the water with out causing disturbances which would have scared away fish. The flat head of Metoposaurus would also allow it to wait at the surface with out easily being seen by predators on the shore. Large groups of Metoposaurus have been found in some areas, in what appear to be pools that were drying out. These animals clustered together in the last remaining water there was during droughts, but alas, the rains didn’t return again in time.
Metoposaurus fairy typical member of the Temnospondyli. This group is known from most of the condiants from the Carboniferous to the Triassic, with some species making it all the way to the Cretaceous. Temnospondyls include the largest amphibians ever known, some of them easily dwarfing Metoposaurus. All of these large forms still spend a lot of time in the water, shown by a variety of skeletal features, such as the weak limbs seen in Metoposaurus. It is uncertain how the temnospondyls are related to the rest of Tetrapoda. They are farther down the tetrapod line than Pederpes, but past this there is a lot of controversy. Some researchers place them as outside of crown tetrapods (modern amphibians + amniotes), while others place them on the line leading to the modern amphibians (frogs, salamanders, and caecilians). It is also very likely that Temnospondyli is not even a natural group, and that some species are closer to amphibians than others.
Did I mention they have really really flat heads?
Recon by Dmitry Bogdanov (DiBgd)
Development mouse embryo over time. I made this gif from this beautiful video.