Evolution News - An Atlas Of The Human Ovary Shows Common Ancestry of Mammals

Ovarian follicle

Human ovarian follicle

First atlas of the human ovary with cell-level resolution is a step toward artificial ovary | University of Michigan News

This piece of research caught my eye, not so much because it refutes creationism with its daft notion of the special creation of humans as separate from all the other animals but because it's reminiscent of the research I used to be involved with in my first profession - a research technician in Oxford University's Department of Human Anatomy.

The research our small group was doing involved the hormonal control of reproduction in guinea pigs, which involved preparing light microscope slides of sections of guinea pig ovaries, and later on, transmission electron micrographs of ovarian tissues.

Like humans, guinea pigs have oestrus cycles where they periodically shed eggs from their ovaries regardless of whether they have mated or not. This is unlike some other mammals which ovulate soon after mating, stimulated to do so by the act of mating. Unlike human females, guinea pigs are only receptive for two or three days before and just after they ovulate. Outside that receptive period, they have a closure membrane that makes penetration impossible.

Unintelligent Design - The Human Curved Birth Canal and Foetal Welfare

Relationship between pelvic depth (i.e. AP length of the pelvis) and spinal curvature as documented in the orthopaedic literature. The pelvis and spine are shown schematically in sagittal view. A Normal spinopelvic relationship where the centre of mass (indicated by the vertical dashed line through the last cervical vertebra, the so-called C7 plumbline) is positioned sagittally above both the hip joints and the superior endplate of the sacrum. B In an anteroposteriorly elongated pelvis (as indicated by the red double arrow) without spinal adjustment, the centre of mass is located behind the hip joints, which compromises the structural stability of upright posture. C To bring the centre of mass back above the hip joints in this elongated pelvis, the sacrum needs to be tilted forward. This leads to an overall increased curvature of the spine, particularly an increased lumbar lordosis and a deviation of the centre of mass from the sacral endplate. Increased lumbar lordosis is associated with multiple orthopaedic disorders, such as spondylolisthesis and disc herniation

Why do humans possess a twisted birth canal? | Universität Wien

A team led by Katya Stansfield from the University of Vienna has shown how the human birth canal evolved as a compromise and was not intelligently designed by an omniscient designer god to be the best solution to the design problem. In fact, it is a shoddy compromise made necessary because the basic human skeleton is an adaptation of the basic quadrupedal vertebrate skeleton and was never designed from the ground up for bipedalism as we would expect of a structure intelligently designed, rather than one evolved from earlier common ancestors with the other great apes and before that, a quadrupedal vertebrate with a horizontal spinal column.

One of the trade-offs was the welfare and survival of the foetus during the birth process. This was put at increased risk in order to ensure the long-term survival of the mother. Creationists might like to think about that as they try to force fit this into their religion with a putative designer god to whom all human life is sacred…

As the University of Vienna press release explains:

Malevolent Designer News - Leaving Nothing To Chance With Alzheimer's Disease

Plasma and brain concentrations of apo B and Aβ.
(A) In vivo PET detection of amyloid binding was used to confirm cerebral amyloid deposition in HSHA mice and their age-matched WT controls. Representative PET and MRI fusion images (coregistered with MRI templates using conventional Fast Spin Echo Sequence T2-weighted sequence) show scan data at 20 to 40 minutes’ post-intravenous administration of [11C] PiB. Each panel (from left to right) illustrates maximum binding potential for [11C] PiB represented by coronal images at −2, 0, 4, and 6 mm from the bregma; indicated by the vertical bar. Plasma (B) and brain (C) levels of apo B, a surrogate marker of TRLs in HSHA and WT control mice, were determined with ELISA. Data are expressed as mean ± SEM. Human and mouse isoforms of Aβ in plasma (D) and brain (E, F) were measured separately with ELISA kits using antibodies specific to each isoform. The data underlying Fig 2B–2F can be found in S1 Data. Aβ, amyloid beta; apo B, apolipoprotein B; HSHA, hepatocyte-specific human amyloid; MRI, magnetic resonance imaging; PET, positron emission tomography; PiB, Pittsburgh compound; TRL, triglyceride-rich lipoprotein; WT, wild-type.

Source: https://doi.org/10.1371/journal.pbio.3001358.g002

Synthesis of human amyloid restricted to liver results in an Alzheimer disease–like neurodegenerative phenotype

According to Creationists, everything about biology and human anatomy and physiology especially, is definitely not the result of natural, evolutionary forces and the operation of random chance. Instead, it is all designed by their reputedly omnipotent, omniscient god who knew exactly what it was designing and designed if for the particular purpose which it serves - which means it is responsible for both the good and the bad in its 'designs', of course.

So, playing at Intelligent [sic] Design advocates for a moment, we have in this scientific paper an example of the sheer mendacious nastiness of Creationism's divine malevolence. It shows how, just to make sure it's victims get Alzheimer's disease in later life, it has designed a mechanism in the liver that manufactures one of the proteins which has been implicated in the progress of this ghastly disease which robs the sufferer of their dignity, their memory, their personality and eventually their life.

The study, published open access in PLOS Biology, was carried out by John Mamo of Curtin University in Bentley, Australia, and colleagues.

According to the press release from PLOS:

Deposits of amyloid-beta (A-beta) in the brain are one of the pathological hallmarks of AD and are implicated in neurodegeneration in both human patients and animal models of the disease. But A-beta is also present in periphereral organs, and blood levels of A-beta correlate with cerebral amyloid burden and cognitive decline, raising the possibility that peripherally produced a-beta may contribute to the disease. Testing that hypothesis has been difficult, since the brain also produces A-beta, and distinguishing protein from the two sources is challenging.

In the current study, the authors surmounted that challenge by developing a mouse that produces human a-beta only in liver cells. They showed that the protein was carried in the blood by triglyceride-rich lipoproteins, just as it is in humans, and passed from the periphery into the brain. They found that mice developed neurodegeneration and brain atrophy, which was accompanied by neurovascular inflammation and dysfunction of cerebral capillaries, both commonly observed with Alzheimer's disease. Affected mice performed poorly on a learning test that depends on function of the hippocampus, the brain structure that is essential for the formation of new memories.

The findings from this study indicate that peripherally derived A-beta has the ability to cause neurodegeneration and suggest that A-beta made in the liver is a potential contributor to human disease. If that contribution is significant, the findings may have major implications for understanding Alzheimer's disease. To date, most models of the disease have focused on brain overproduction of A-beta, which mimics the rare genetic cases of human Alzheimer's. But for the vast majority of AD cases, overproduction of A-beta in the brain is not thought to be central to the disease etiology. Instead, lifestyle factors may play a more important role, including a high-fat diet, which might accelerate liver production of A-beta.

Continuing Human Evolution

Sketch of median artery vessel which supplies blood to the human forearm and hand.

Credit: Professor Maciej Henneberg

Forearm artery reveals human evolution continues – News

Three scientists from Flinders and Adelaide Universities, Australia, have found evidence of continuing human evolution in the increasing occurrence in adults of an artery known as the median artery, in the forearm. The median artery begins as the main blood supply to the developing forearm but normally atrophies in the embryo when the role is taken over by two other arteries - the radial and ulnar arteries.