With its blood-shot eyes and dazed demeanour, the quick tempered creature is easy to spot as it prowls around town, scowling at fellow members of its species who seem energised and carefree...
Yes, it's the sleep deprived parent!
Before I became a father five years ago I had no idea that I too would turn into one of these reproductive zombies.
I never realised how much I would long for a good night's sleep.
Back then when you asked me what might improve my quality of life it might be a new house, a luxury holiday or a better car. Now I would trade them all for one chunky lie-in.
When our first baby arrived my childless friends chuckled at my inability to cope with daily tasks after another night peppered with bouts of crying from our newborn. But their smirks faded as they themselves began to have babies. As my younger brother put it: "People with children tell you how tired you'll be when you become a parent, but you just don't get it until you experience it at first hand."
Research shows that new parents lose out on more than six weeks worth of sleep in the first year of having a baby.
Mums have it worse than dads, especially with all that breastfeeding to do - figures show that new mothers get less than four hours sleep a night.
To be fair our baby boy was unusually wakeful. A newborn is supposed to sleep for an average of 16 hours. He barely managed six hours a night. Indeed he got so little sleep for the first 18 months that we began to worry about his brain developing properly.
Several years later, and with his brain seemingly functioning perfectly normally, it's my own grey matter I'm more worried about. Because, with a two-year-old in tow now as well, getting an uninterrupted night's sleep in our household is still seriously rare.
In fact, when it does happen, we're so shocked that we run to our children's bedsides to make sure they are still alive, only to wake them up by mistake and ruin the extra kip we could have had.
When they were babies it was, of course, feeding that was the main issue.
These days there seems to be no end of reasons for their waking up: needing to go to the toilet, night terrors, nightmares, illness, falling out of bed or, most recently, sleepwalking.
The other night I heard a noise on the landing and was freaked out to find my five-year-old on the other side of the bedroom door starring wide eyed back at me oblivious to where he was. When I asked him if he was alright he screamed, then told me off for waking him up.
While our pair seem to be thriving despite their erratic sleep patterns the lack of shut-eye is definitely taking its toll on the two of us.
Scientists agree that not getting enough sleep is bad for your health. We should be getting about eight hours a night, but we're lucky to get six.
Apart from meaning we look several years older than we're supposed to, the worst effect seems to on our ability to function as normal human beings during the day. By her own admission my wife's memory is shot to pieces – and she is constantly leaving her car keys in the fridge.
I'm no better. Recently, I went shopping in the supermarket, but was so tired that half way through I picked up someone else's loaded trolley and marched off to the check out. I only realised my mistake half way through loading the items on to the conveyer belt when I realised I'd never buy dog food, as we don't have one.
Everything suffers when you are sleep deprived. We stumble through the working day, then feel guilty that we don't have the energy to enjoy playing with the children as much as we should.
It can be dangerous too. A Channel 4 survey found that nearly 45 of dads have done this.
Of course, we're not alone. Half of families say lack of sleep has left them feeling exhausted – it's a national epidemic.
I'd like to think that as my boys get older the problem will go away. Bring on the teenagers that won't get out bed I say. But then I read that parents actually have most sleepless nights when their child is aged 18-30, when we lie there worrying if they are getting into trouble or driving safely.
One survey concluded that by time a child is 30, parents have had 1,872 sleepless nights. In which case I'm owed a rest – I'm pretty sure I hit that target long ago.
More on Parentdish: Toddlers and sleep problems
How not to punch people when you have a baby who does not sleep