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Lizards and humans 'share sleep patterns'
australian dragon
Lizard sleep appears to be much simpler, which could mean it is closer to the ancestral mode of brain sleep.
REM and slow wave sleep could date back 230 million years

Lizards share sleep patterns with humans, scientists have said, as they described rapid eye movement (REM) sleep and slow wave sleep in a reptile for the first time.

Behavioural sleep is seen in all animals, from humans to insects, but in people, sleep is characterised by periods of slow wave brain activity followed by short phases of REM sleep. These electrical features are not well understood and had previously only been described in humans and birds.

Writing in the journal Science, a research team from the Max Planck Institute for Brain Research in Germany described REM and slow wave sleep in an Australian dragon (Pogona vitticeps).

Lizard sleep patterns were found to share many common features with mammals, including a phase characterised by low frequency/high amplitude average brain activity and rare and bursty neuronal firing (slow wave sleep). Another phase was characterised by awake-like brain activity and rapid eye movements. During slow wave sleep, coordinated activity of cortex with another area was seen. In mammals, that other area is the hippocampus, while in lizards it was the so-called dorsal ventricular ridge.

Some interesting differences were also seen. Lizard sleep rhythms were very regular and fast and the sleep cycle lasted for about 80 seconds, compared to 30 minutes in cats and 60-90 minutes in humans.

In lizards, the duration of REM and slow wave sleep are roughly equal in each cycle, but in mammals, REM is much shorter than slow wave. Both are short and irregular in birds.

On the whole lizard sleep appears to be much simpler, which could mean it is closer to the ancestral mode of brain sleep. Scientists believe it is likely to point towards common origins for mammals, reptiles and birds, rather than a separate, convergent evolution. REM and slow wave sleep may therefore be traced back at least 230 million years to the common ancestor of reptiles, birds and mammals.

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Vets to run marathon for World Animal Protection

News Story 1
 Two recently graduated veterinary surgeons will be running the London Marathon in April to raise money for the charity World Animal Protection.

Alex Bartlett and Maeve O'Neill plan to run the race together if they are given the same start times.

Dr O'Neill said: "You're always limited in what you can do to help animals, so it is nice to raise money for a charity that helps animals around the world."

Dr Bartlett added: "I have never run a marathon before and am excited to run my first one for such a good cause!"

Both Dr Bartlett and Dr O'Neill have fundraising pages online. 

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BSAVA releases new Guide to Procedures

The British Small Animal Veterinary Association (BSAVA) has published a new edition of its Guide to Procedures for Small Animal Practice.

It has added four new procedures; cystostomy tube placement, endotracheal intubation, point-of-care ultrasound and wet-to-dry dressings.

BSAVA says that it is an essential step-by-step guide to diagnostic and therapeutic procedures performed in practice. The textbook includes new images and illustrations, as well as high-definition videos for use prior to procedures.

Nick Bexfield and Julia Riggs, editors of the new edition, said: "We have built upon the success of the previous editions by responding to the feedback received from the BSAVA readership, and hope this new guide helps to further increase the confidence and accuracy with which these procedures are performed."

Print copies are available in the BSAVA store, with a digital version in the BSAVA library.