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Sciences

Natural history - from animals to minerals, fossils to sea slugs. MV's scientists use the state's collections in important research.

Five bright planets in the morning sky

Author
by Tanya Hill
Publish date
22 January 2016
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For the first time in more than 10 years, it will be possible to see all five bright planets together in the sky. Around an hour or so before sunrise, Mercury, Venus, Mars, Jupiter and Saturn, the five planets that have been observed since ancient times, will appear in a line that stretches from high in the north to low in the east.

Five bright planets Mercury rises out of the early morning glow to complete the full set of five bright planets.
Source: Museum Victoria/Stellarium
 

The planets are visible from right across Australia in the dawn sky. You can start to look for the lineup from Wednesday, January 20 and it can be seen right through until the end of February.

Venus, Mars, Jupiter and Saturn have been in the morning sky since the beginning of the year. Jupiter is bright in the north, next comes reddish Mars, followed by pale Saturn and lastly brilliant Venus, which shines above the eastern horizon. It is the appearance of Mercury that makes the family complete.

Mercury has just transitioned from an evening object to a morning object. At first it will appear quite low to the eastern horizon and of all the planets it is also the faintest, so it will be hard to see to begin with. However, Mercury will continue to rise higher each morning and by early February it will sit just below bright Venus.

Dates with the moon

If you need something a little more to get you leaping out of bed before sunrise, then here are the dates to mark in your calendar. From the end of January, the moon will travel by each planet and can be used as an easy guide for your planet-spotting.

The moon passes by the planets From January 28 through to February 7, the waning moon will travel through the line up of planets, passing each one in turn.
Source: Museum Victoria/Stellarium
 

On January 28, the moon will be right next to Jupiter. Come February 1, the moon (in its Last Quarter phase) will be alongside Mars, then on the following morning it’ll sit just below the red planet. On the morning of February 4, the crescent moon will be near Saturn. Then on February 6, the moon will be alongside Venus and on February 7, a thin sliver of moon will sit below Mercury.

In line with the sun

The line formed by the planets in the sky closely follows the ecliptic, the apparent path of the sun against the background stars. This path marks the plane of our solar system, visual proof that the planets, including Earth, all orbit the sun on roughly the same plane.

The ecliptic is bordered by the constellations of the zodiac and one of the most recognisable zodiac constellations is Scorpius. If you’re awake before the first rays of the sun begin to drown out the stars, then look for the curved outline of the scorpion between Mars and Saturn. In fact, sitting just above Saturn is the red supergiant star Antares, which marks the heart of the scorpion and its reddish colour makes it the perfect rival for Mars.

Rare oddity

It’s been a long time since the orbits of all five planets have brought them together to the same patch of sky. To make the best of the viewing opportunity try and get to a clear open space where you can see from the north all the way across to the eastern horizon.

Position of the planets Position of the planets in their orbits around the sun as of February 2016.
Source: from www.theplanetstoday.com
 

As early February comes around, I also highly recommend checking out the flight path of the International Space Station via websites such as Heavens Above or NASA’s Spot the Station.

The Station will be flying morning passes over Australia during that time and current predictions for each capital city have it travelling right through or near the line of planets, for example: Darwin (February 3), Brisbane (February 5), Perth (February 6), Sydney (February 7), Canberra (February 7), Adelaide (February 8), Melbourne (February 9) and Hobart (February 11). The predictions can change slightly, so best to check the websites closer to the date and be sure to enter your precise location to obtain the most accurate timing for the pass.

Finally, there’s still more to come. This August the five planets will be together again, visible in the evening sky, so stay tuned for more planet watching in 2016.

The Conversation

Tanya Hill, Honorary Fellow of the University of Melbourne and Senior Curator (Astronomy), Museum Victoria

This article was originally published on The Conversation. Read the original article.

Nudibranch guide

Author
by Mel Mackenzie
Publish date
9 December 2015
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If you’ve ever scuba-dived under Blairgowrie pier or taken a close look at a clump of seaweed on a rock-pool ramble you may have been lucky enough to spot one of these extraordinary creatures.

Colourful nudibranch Various nudibranch Left: Sagaminopteron ornatum: Sea slug, Source and Photographer John Chuk. Right: Phyllodesmium macphersonae: Sea slug, Photographer: Planton Vafiadis.  

These tiny “butterflies of the sea” are actually related to snails, though as most are lacking a shell their common name ‘nudibranch’ refers to their naked or exposed gills.

Colourful nudibranch Nudiibranch: Left: Flabellina sp. 4: Sea slug, Source and Photographer: John Chuk. Right: Trinchesia sororum: Sea slug, Photographer: Planton Vafiadis.

Our local marine parks and sanctuaries play host to a huge variety of over 400 nudibranch and related animals, from bubble shells, sea hares, side-gilled and sap-sucking slugs, to the true nudibranchs. The expert when it comes to all of these is the one and only Robert (Bob) Burn. With over 60 years spent collecting, observing and studying these animals, Bob has channelled a life-time of work into creating a fantastic new field-guide (Nudibranchs and related molluscs) to introduce us to these gorgeous marine critters.

Nudibranch Left: Philine sp. 2: Sea slug. Right: Polycera sp. 2: Sea slug.
Image: Platon Vafiadis
Source: Platon Vafiadis 2008

Thanks to Bob’s knowledge of the group, and the amazing contributions of many talented collectors and photographers, the guide is filled with fabulous images, descriptions, identification keys and fun facts to help any keen amateur naturalist, diver or photographer. A fun fact you ask? How about their ability to collect deadly nematocysts from their cnidarian food sources and squirrel these away for future defence? Or their reproductive strategies from hermaphroditic mating to gathering in “frothy orgiastic groups”?  With gorgeous colours, stripes, spots and fringes, many nudibranchs are also extremely good at hiding, so next time you snorkel past a sponge, hydroid or clump of seaweed on a pier pylon, take a closer look… a sneaky pair of head tentacles (rhinophores) may just give one away.

Nudibranch Left: Noumea haliclona: Sea slug. Right: Placida sp. 1: Sea slug.
Image: John Chuck
Source: Copyright John Chuk 2005
 

The field guide is available from MV shops or online, the perfect gift for Christmas!

About the Author:

Geelong building contractor by day, but world nudibranch expert at all times, Bob Burn is an Honorary Associate at Museum Victoria and long-time member of the Marine Research Group of the Field Naturalists Club of Victoria and the Malacological Society of Australasia. He is the author of over 100 publications on nudibranchs and other molluscs and has described over 90 species of these amazingly diverse marine invertebrates. 

Collecting specimens at sea Bob Burn 2012 Murrels Beach
Image: Leon Altoff
 

Bob Burn searching for nudibranchs at Murrel’s Beach. Photo: Leon Altoff Source: Museum Victoria.

People in photographs Left: Bob with friend, mentor and fellow marine icon Hope Black. Right: Bob with Mark Norman and Robin Wilson.
Source: Museum Victoria
 

About Museum Victoria Field Guides

Nudibranchs is part of the Museum Victoria field guide series. Each guide in the series covers a different group of marine animals, featuring the common species within that group. Most of the animals described occur in shallow waters, on shores and reefs along the coastline of the southern half of Australia and beyond. The series are supported by the Australian Government through a grant from Natural Heritage Trust, and this particular guide was also supported by a grant from the Norman Wettenhall Foundation.

Field guides Field guides of Museum Victoria.
Source: Museum Victoria
 

Want more guides for your summer at the beach? Download the free Museum Victoria apps or take a look at the Port Phillip Bay Taxonomic toolkit.

How cute is that?

Author
by Patrick
Publish date
19 October 2015
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Melbourne Museum recently participated in the global #Cuteoff on Twitter, where researchers from around the world posted photos of their supposedly ‘cute’ study animals. Given that many of these posts featured snails, turtles, spiders, squid and sea sponges, it begs the question whether cuteness is in the eye of the beholder.

Whipbird chick This baby Whipbird (Psophodes olivaceus) from the Forest Gallery is small, fluffy and vulnerable – in other words quite cute.
Image: Patrick Honan
Source: Museum Victoria

Konrad Lorenz, the pioneering ethologist, first dissected cuteness in the 1940s with the concept of Kindchenschema (‘baby schema’), identifying that juvenile, or paedomorphic, traits are the key. From an evolutionary point of view, paedomorphic traits are a significant advantage to very young individuals, as they push the buttons of adult humans, encouraging their nurturing side. Cuteness in humans can be further broken down as the sum of certain traits (tiny chin and nose, chubby cheeks, large eyes and rosy complexion), where each element is a cumulative index of cuteness. When these features are enhanced in photos of adult subjects in scientific experiments, observers see the subjects as progressively cuter and report increasingly pleasurable and caring emotions.

Tawny Frogmouth Blinky, one of the Forest Gallery’s Tawny Frogmouths (Podargus strigoides). Blinky has large, wide-set eyes and a disproportionately large head, making him definitively cute.
Image: Chloe Miller
Source: Museum Victoria

The propensity to nurture cuteness is also applied by humans to other animal species with the same traits. Animals that have a flat face, short nose, large ears and large, expressive, wide-set forward-facing eyes are too irresistible to refuse. And the more exaggerated these features, the more appealing they are, as demonstrated by the Hello Kitty phenomenon and kawaii culture in Japan. A number of theories suggest many breeds of cats and dogs have been selectively bred to emphasise these characters, and this appears to be easier than you might think.

Silver Fox The Silver Fox (Vulpes vulpes)
Image: Zefram
Source: Creative Commons: CC-BY-SA-3.0

In 50 years of experiments in the Soviet Union, scientist Dimitri Belyaev domesticated the Silver or Siberian Fox, a silver morph of the Red Fox (Vulpes vulpes). By choosing the tamest offspring from each litter, i.e. individuals that were less likely to flee or more likely to whimper and sniff and lick the handler, Belyaev also inadvertently selected the retention of paedomorphic traits. After 40 generations the foxes had larger, floppy ears, shorter or curly tails, and shorter snouts.

Pobblebonk The large, toad-like Pobblebonk (Limnodynastes dumerilii) upping its cuteness index by adopting a tap dancer’s stance.
Image: Melvin Nathan
Source: Museum Victoria

Animals that are not otherwise cute can, in certain situations, enhance their cuteness factor by adopting human attitudes or being associated with familiar human objects.

Alpine Blue-tongue Lizard The comportment of Beth, an otherwise cranky Alpine Blue-tongue Lizard (Tiliqua nigrolutea), can be significantly softened and her cuteness improved when wrapped in a towel.
Image: Chloe Miller
Source: Museum Victoria

Healthy juvenile traits also play a role in cuteness – clear eyes, smooth skin, a pink glow (i.e. sufficient blood circulation) and bilateral symmetry. However, a helpless baby animal obviously in recovery from an illness or injury does sometimes press additional buttons.

Mountain Dragon The Mountain Dragon Falcor (Rankinia diemensis). Although not particularly cute on his own, the bandage raises Falcor’s cuteness factor several fold.
Image: Melvin Nathan
Source: Museum Victoria

Animals that can clearly look after themselves fail to evoke the cute response. Venomous animals, such as spiders and snakes, for example, or spiky or heavily armoured animals, require no nurturing from us. Animals with fewer than four legs, such as worms, or animals with more than four legs, such as centipedes, also elicit no empathy.

Prickly Katydid The antithesis of cuteness. The Prickly Katydid (Phricta spinosa) is laden with spikes and other armour, and well able to look after itself.
Image: Patrick Honan
Source: Patrick Honan

Charities and wildlife groups latched on to the cute factor many years ago. For an endangered species, being cute is definitely an evolutionary advantage these days. A baby panda or harp seal will always get more attention and funding than an endangered snail or spider. According to Canadian ecologist Ernie Small, this is skewing the world’s conservation efforts (and biodiversity in general in the long run) towards the cute and fluffy. It’s reflected in the dollars spent on saving endangered species – highest for the charismatic megafauna and lowest for reptiles, invertebrates and plants, with the number of paedomorphic traits directly proportional to the dollars spent. Ernie Small goes as far as listing the features that will boost a conservation project.

Mitchell's Hopping Mice The cute-as-hell Mitchell’s Hopping Mice (Notomys mitchelli) behaving cutely. This species is listed as ‘Near Threatened’ in Victoria.
Image: Patrick Honan
Source: Museum Victoria

So it’s no wonder all researchers want their study animals to be the cutest. Perhaps social scientist Paris Hilton said it best: “The only rule is don’t be boring and be cute wherever you go. Life is too short to blend in”.

Meet Hyorhinomys stuempkei, a Hog-nosed Rat

Author
by Web Team
Publish date
9 October 2015
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As part of an international research team, Museum Victoria scientists have discovered a new species of mammal: a hog-nosed rat named Hyorhinomys stuempkei.

Discovered in a remote and mountainous area of Sulawesi Island in Indonesia, the Hog-nosed Rat, Hyorhinomys stuempkei, is a new species of mammal previously undocumented in any scientific collection.

Hyorhinomys stuempkei Hyorhinomys stuempkei
Image: Kevin Rowe
Source: Museum Victoria
 

The new species has such a unique anatomy and is so genetically different from other species that it was described not only as a new species but a new genus (a step above a new species). The team’s research will be published as the cover story of the October edition of Journal of Mammalogy.

Discovered by an international team comprising Dr. Kevin Rowe (Museum Victoria); Heru Handika (Museum Victoria); Anang Achmadi (Museum Zoologicum Bogoriense), and Dr. Jacob Esselstyn (Louisiana State University Museum of Natural Science), this new discovery is the third new genus described by this international collaboration since 2012, and identifies a rodent with features never before seen by science.

Let yourself get acquainted with the "charismatically different" Hyorhinomys stuempkei, "like no other rat that's been seen on Sulawesi", courtesy of two of its discoverers, Museum Victoria's Dr. Kevin Rowe and the LSU Museum of Natural Science's Dr. Jacob Esselstyn.

The interest in the Hog-nosed Rat's discovery has been phenomenal on news sites and on digital and social media, including the BBC, Time, CNN, The Guardian, The Press Association, Al Jazeera, ABC radio and TV, The Age, The Guardian, the Jakarta Post, the Daily Mail, Mirror, the Independent and The Australian.

A media release, "Museum Victoria Scientists Announce Discovery of a Hog-nosed Rat", is available on the MV website.

Hawks vs. Eagles: who will win … according to SCIENCE?!

You’ve all heard of the big match taking place this weekend between the Hawthorn Hawks and the West Coast Eagles. The speculation is rampant – who is going to take home the Cup in 2015? 

Hawks vs. Eagles Hawks vs. Eagles...who will win?

At Museum Victoria we can’t tell the future but we do know our native animals. So we began to wonder – who would win if the match ascended from the grassy green of the MCG and took place between their mascots in the sky?

Firstly, because we’re scientists we need to establish the facts.

What species are we talking about?

Eagles:
There are three species of eagle in Australia – the Wedge-tailed Eagle (Aquila audax), White-bellied Sea Eagle (Haliaeetus leucogaster) and the Little Eagle (Aquila morphnoides). The first two are the largest raptors (birds of prey) in Australia. They all belong to the Accipitridae family, along with the other fifteen bird of prey species, except for owls, falcons and kestrels.

Hawks:
Within the same Accipitridae family Australia also has buzzards, kites, goshawks, sparrowhawks, osprey, bazas and harriers, but no species that actually goes by the common name ‘Hawk’. The colloquial term hawk can refer to many of these birds but is often also used to refer to birds outside this group.

We’re working with some loose definitions here (not ideal for scientists, as I’m sure you can imagine) but let’s presume that the goshawks and sparrowhawks are what qualifies as Australian hawks.

Thus our Grand Final showdown is set to take place between the largest eagle – the Wedge-tailed Eagle and the largest hawk – the Red Goshawk.

Big game strategy:
Eagles will spend hours circling at a distance before moving in for the kill. Hawks tend to hunt from concealed hiding places, attacking by stealth and finishing with a high speed chase.

Size and speed:
In this particularly case our Eagle is about five times the size of our Hawk. Eagles are also marathon flyers and can keep going for hours. Hawks are fast over short distances but will tire easily.

Intelligence:
Hawks are very intelligent birds, second only to the Adelaide Crows. This has been established by Dr Louis Lefebvre of McGill University in Canada who developed the world’s only comprehensive avian IQ index. Eagles are also very intelligent…but not as intelligent as a Hawk.

Eyesight:
Unlike umpires, Hawks also have excellent eyesight. They have five times as many photoreceptors as humans and ten times better eyesight, partly due to an indented fovea that magnifies their centre of vision. This superior intelligence and eyesight means that they are favoured over eagles by falconers. Eagles also have excellent eyesight, and are known to soar 2km above the ground searching for carrion or prey. But…their eyesight is not as good a Hawks.

Flexibility and adaptability:
Eagles are very large and their weight and power works against their flexibility in close quarters. But with a good run-up they are almost unstoppable. Hawks are more readily able to change strategy to reflect changing circumstances, to start and stop quickly, and to win against their opponents in tight struggles.

Game tactics:
Eagles consume a large part of their diet as carrion, which doesn’t require much intelligence. They also feed on large animals such as North Melbourne Kangaroos, which they overcome through brute force … and dubious umpiring decisions. Hawks feed mostly on birds, especially parrots, which are smart in their own right and require more intelligence to overcome.

So who’s going to win? We’ll have to wait and see, but rest assured that feathers will fly!

Prehistoric marine life in Australia’s inland sea

Author
by Melanie Raymond
Publish date
2 September 2015
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Cover of Prehistoric marine life in Australia’s inland sea
Cover of Prehistoric marine life in Australia’s inland sea
Source: Museum Victoria
One hundred million years ago, Australia was not so much a continent, as a series of islands interconnected by vast shallow waterways. In place of our central deserts, lay great expanses of water, the legendary ‘inland sea’ once sought by European explorers a hundred million years too late. The Eromanga Sea teemed with a rich and diverse fauna and flora which left their remains to fossilise on the bottom of the ancient sea floor.


We didn’t end up using this blurb but it did catch my interest. Danielle Clode, a science writer and previous Thomas Ramsay Fellow at Museum Victoria, sent it to me as part of her sales pitch for a new title. That title, now called Prehistoric marine life in Australia’s inland sea, has just been published. It is the third book in the Museum Victoria Nature series.

The first book was Tom Rich’s Polar Dinosaurs and the second, Danielle Clode’s Prehistoric giants. The megafauna of Australia. The latter was shortlisted in the prestigious CBCA awards in 2008 and continues to be a bestseller for Museum Victoria Publishing.

Platypterygius australis: Ichthyosaur Platypterygius australis skull and rostrum specimen. An extinct ichthyosaur from the Cretaceous period.
Image: Jon Augier
Source: Museum Victoria
 

Prehistoric marine conjures up the vanished world of the Aptian/Albian period. Written for a young audience who may never have heard of the Eromanga Sea, Prehistoric marine introduces us to a foreign landscape and its inhabitants. Monstrous Kronosaurus queenslandicus ruled the shallow inland seas, and other sharp-toothed predators, including sharks and ichthyosaurs, cruised around, looking for prey. On the sea floor, there was also an abundance of life, including the impressive Tropaeum imperator, an ammonite which measured up to 75 cm wide and was mistaken for a tractor tyre when first discovered.

Platypterygius australis cartilage muscle overlay Reconstruction of platypterygius australis, an ichthyosaur from the Cretaceous period with cartilage muscle overlay showing developmental process of drawings.
Image: Peter Trusler
Source: Peter Trusler
 

You can hear Danielle talk about her book with Robyn Williams on ABC Radio National's Science Show.

  Artist's interpretation of a Kronosaurus catching a pterosaur Prehistoric marine creature Kronosaurus (similar to a crocodile) leaping out of the ocean to catch a pterosaur
Image: Tor Sponga
Source: Bergens Tidende
 

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