Parthenogenesis - Virgin Births in Nature

Parthenogenesis

How do you really reproduce without sexual reproduction? Asexual reproduction, of course. Simple, really… but not for the females of some species.

There are loads of links in this post, so click on them to learn more.
Some plants, insects, shark and lizard species are known to reproduce by parthenogenesis - embryo development is carried out without fertilisation by a male -so called ‘virgin creations.’

Parthenogenesis can take a range of pathways :

The egg can be fertilised by a polar body (a ‘leftover’ of egg production), making the chromosome number diploid and triggering embryo development. Here is a simple explanatory animation from amateurmicrography.net.
Chromosomes in the egg can self-replicate, making up the diploid number and the embryo develops from there.
Other methods include suppression of male genotypes (technically still sexual reproduction?), or eggs cells dividing by meiosis.

The resulting offspring are going to be all the same gender. In some species, the XY system determines gender and parthenogenesis produces all females. In other, the ZW system dictates that they will all be male.

Parthenogenesis is a reproductive strategy that sacrifices the genetic variation (a driving force of evolution) of sexual reproduction for the simple ability to reproduce. Small invertebrates, such as aphids, can use it to produce large numbers of females very quickly.
Larger organisms, such as Komodo dragons (Indonesia link!), have been known to use parthenogenesis in the absence of males, producing an all-male clutch of eggs. It is thought that this might allow them to set up new populations on isolated islands, using just a single female. Here’s a quick video of a Komodo dragon parthenogen hatching:



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Sophie Ellis-Bextor survives pre-eclampsia scare again to have second child nine weeks early

Sophie Ellis Bextor has given birth two months prematurely after she was diagnosed with a life-threatening condition.
It is the second pregnancy scare for the 29-year-old singer and daughter of former Blue Peter presenter Janet Ellis.
Her four-year-son Sonny was also born nine weeks early.
Doctors had to perform an emergency caesarean to deliver her second son, named Kit Valentine Jones, who weighed 2lb 10z. He was immediately placed in an incubator.
Sophie had been diagnosed with pre-eclampsia, which in severe cases can cause the death of the mother and unborn baby.

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Details of Kit's dramatic arrival were revealed on BBC Breakfast yesterday by his grandmother, who let the news slip as she was discussing the role of grandparents.

Janet, 53, said: 'Sophie's just had her second little boy. He was early, nine weeks early, but he is doing fine. He is doing very well.'

Sophie, who is married to The Feeling's bass guitarist Richard Jones, was admitted to the private Portland Hospital in London last week on her doctor's advice. Kit was delivered on Saturday.

Outside the couple's West London home yesterday, Richard, 29, said: 'I'd be lying if I said it wasn't stressful.
'It has been dramatic, but we are very happy. We are a lot calmer this time because we have been through it all before. I'm pretty tired, I've been all my time at the hospital and I've just come home to get some stuff.
'It has been hard, but it's been helped because Sonny has been amazing, even though it's been so tough.'

Sophie revealed they were expecting their second child on November 5th last year and that it was due in April.
Sonny spent five weeks in hospital before being allowed home. Their troubles weren't over as he Sonny developed meningitis at four months and had to be readmitted to hospital. Sonny went on to make a full recovery.

Pre-eclampsia causes high blood pressure and can lead to stroke, blood clotting and kidney, liver and lung problems in pregnant mothers.


Sophie's mother Janet Ellis spoke on the radio about Kit's dramatic arrival

In an online blog about her second pregnancy Sophie said: 'Protecting myself and the baby is the most important thing at this time and being pregnant really does give you the chance to slow down, prepare for the birth and focus on the things you really want to do.'

She added: 'The hardest part of the pregnancy so far has been before I could announce I was actually pregnant. I'm always a bit cautious of getting coughs and colds when I'm pregnant as they seem to take that bit longer to shake off so I'm dosing up on the vitamins as it's so cold outside.

'I suffered from pre-eclampsia in my first pregnancy so I am having regular scans at the moment.'

She also revealed that her son could not wait for a younger sibling.
'We are all really excited about meeting the new addition to our family. Sonny has always loved babies and has been telling me for a while he would like a baby brother or sister so for him it's what he expected would happen at some point.'

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