From a female perspective, pregnancy is always a huge investment. Even more so if her species has a hemochorial placenta. Once that placenta is in place, she not only loses full control of her own hormones, she also risks hemorrhage when it comes out. So it makes sense that females want to screen embryos very, very…
Inside the uterus we have a thick layer of endometrial tissue, which contains only tiny blood vessels. The endometrium seals off our main blood supply from the newly implanted embryo. The growing placenta literally burrows through this layer, rips into arterial walls and re-wires them to channel blood straight to the…
...regular endurance exercise leads to four major consequences: Increased ability of the heart to eject blood increased ability of the blood vessels to send blood to where blood is needed Increased number of capillaries (the vessels that deliver oxygen and ‘food’ to the muscles) increased size and the number of…
Given the invasive nature of pregnancy, it’s perhaps not surprising that the primate womb has evolved to be wary of committing to it. Mammals whose placentae don’t breach the walls of the womb can simply abort or reabsorb unwanted foetuses at any stage of pregnancy. For primates, any such manoeuvre runs the risk of…
In most mammals, the mother’s blood supply remains safely isolated from the foetus. It passes its nutrients to the foetus through a filter, which the mother controls. The mother is a despot: she provides only what she chooses, which makes her largely invulnerable to paternal manipulation during pregnancy. In primates…
The first thing you'll notice about Real-life is that it about 9 months to start a new character, mainly because two other players have to "register" for a new player to enter the game, fortunately now-a-days "registering" is happening more and more frequently, unfortunately this means that the "sever" getting…
What's more, most males could not possibly afford to buy a woman's reproductive potential if courtship were a simple economic exchange. What would be an appropriate market price for a nine-month pregnancy, the pain of childbirth, the exhaustion of breast-feeding, and twenty years of maternal care? At least half a…
Even something that has been traditionally seen as the purview of the young—the ability to learn new languages —continues to change the landscape of the brain late into life. When a group of adults took a nine-month intensive course in modern standard Chinese, their brains’ white matter reorganized progressively (as…
Having heard the poem, Monkey went up to him and said, "Master, you only know about the moon's beauty, and you're homesick too. You don't know what the moon's really about. It's like the carpenter's line and compasses−−it keeps the heavenly bodies in order. On the thirtieth of every month the metal element of its male…
Careful and reproducible observations and measurements in the bbiosciences have similarly forced us to repeatedly refine our traditional ideas about what life itself is and when it begins. Is a human being first a life when it emerges from the birth canal? Does it have any legal rights is as a person before then? Or…
[I]magine you want to know the sex of your unborn child. There are several approaches. You could, for example, do what the late film star ... Cary Grant did before he was an actor: In a carnival or fair or consulting room, you suspend a watch or a plumb bob above the abdomen of the expectant mother; if it swings…
The most fundamental innovation is the evolution of another fluid-filled sac, the amnion. in which the embryo floats. Amniotic fluid has roughly the same composition as seawater, so that in a very real sense, the amnion is the continuation of the original fish or amphibian eggs together with its microenvironment, just…
Man has two conditions of existence in the body. Hardly two creatures can be less alike than an infant and a man. The whole fetal state is a preparation for birth ... The human brain, in its earlier stage, resembles that of a fish: as it is developed, it resembles more the cerebral mass of a reptile; in its increase…
Mary Shelley’s idea of the mind was, like Lawrence’s, based on the notion of the strictly physical evolution of the brain. This is how Lawrence was provocatively challenging his fellow members of the Royal College of Surgeons in his lectures of 1817: ‘But examine the “mind,” the grand prerogative of man! Where is the…
Lawrence eventually went on to broaden his attack. Science, he argued, had an autonomous right to express its views fearlessly and objectively, without interference from Church or state. It must avoid ‘clouds of fears and hopes, desires and aversions’. It must ‘discern objects clearly’ and shun ‘intellectual mist’. It…
Vestigial genes can go hand in hand with vestigial structures. We mammals evolved from reptilian ancestors that laid eggs. With the exceptions of the “monotremes” (the order of mammals that includes the Australian spiny anteater and duck-billed platypus), mammals have dispensed with egg-laying, and mothers nourish…
One of my favorite cases of embryological evidence for evolution is the furry human fetus. We are famously known as “naked apes” because, unlike other primates, we don’t have a thick coat of hair. But in fact for one brief period we do—as embryos. Around sixth months after conception, we become completely covered with…
For evolutionary reasons, human babies were never meant to be born and raised in isolation from a group. Psychotherapist Ruth Josselson believes it is especially important for young mothers to create and maintain an active social tribe after giving birth. There are two big problems with this suggestion: 1) Most of us…
Researchers have isolated three toxic types. Their common characteristic: that you feel out of control over the bad stuff coming at you. As stress moves from moderate to severe, and from acute to chronic, this loss of control turns catastrophic and begins to affect baby. Here are the bad types of stress: • Too…