Prawns have individual personalities, new study

This 2012 video shows rockpool prawns feeding.

From the University of Exeter in England:

Cautious prawns win battle for food

June 1, 2018

Prawns have personalities — and cautious crustaceans do better in the battle for food, new research shows.

Scientists from the University of Exeter studied rockpool prawns (Palaemon elegans) and found some were consistently shy, while others were bolder.

But this bravery may come at a cost — as the risk takers tended to do worse than other prawns when competing for food.

“We found that the shyer prawns were better at controlling a food source”, said first author Daniel Maskrey, formerly of the University of Exeter but now at the University of Liverpool.

“This means that when they found food and possible rivals were nearby, they stayed and fed for longer than bolder prawns.

“The reasons for this aren’t clear, but it’s possible that bolder prawns have a higher urge to go on and continue exploring.

“We witnessed prawns fighting over food, and it could be that some use a bold exploration strategy because they favour searching for new food over competing with stronger rivals.”

Boldness was tested by repeatedly putting prawns into an unfamiliar tank and seeing how much they explored and ventured into the middle.

Dr Tom Houslay, of the Centre for Ecology and Conservation on the University of Exeter’s Penryn Campus in Cornwall, said the study could help scientists understand why members of one species — and even the prawns in a single rockpool — have different personalities.

“Some individuals are more successful at monopolising food, while others are more willing to engage in potentially risky exploration,” he said.

“In different conditions and situations, either of these strategies might pay off — which might explain why evolution has not led to a single personality type.

“The rockpools where these prawns live change with each high tide, and having such variation among prawns could be crucial when it comes to adapting to these and other changes.”

The prawns in the study were all from Gyllyngvase beach in Falmouth, and their feeding behaviour was tested using parcels of brine shrimp. Prawns were split into groups of similarly sized individuals to compete for access to food.

Boys save roe deer from drowning

This 1 June 2018 video is about a male roe deer swimming in a canal near Noordseschut village in Drenthe province in the Netherlands.

The animal could not climb out of the water as the banks were too high. The deer got tired and threatened to drown.

Then, three boys jumped into the water. One of them put the roe deer on a bank. After resting for five minutes on the bank, the deer ran away,

Oldest amphibians not in freshwater

This 2015 video is called Ancestral Evolution – Ichthyostega to Varanops.

By Carolyn Gramling, 5:29pm, May 30, 2018:

The first land-walking vertebrates may have emerged from salty estuaries

An analysis casts doubt on views that the ancient creatures arose in freshwater

Earth’s earliest land-walking vertebrates didn’t paddle about in freshwater lakes or rivers. Instead, these four-footed creatures, which appeared about 375 million years ago, lived in the brackish waters of an estuary or delta, researchers report online May 30 in Nature.

Early tetrapods, such as Ichthyostega and Acanthostega, lived an amphibious existence between land and sea: They had feet, but also gills and tails made for swimming. A new study by paleontologist Jean Goedert of Université Lyon in France and colleagues suggests that the animals also could have tolerated rapid changes in salinity, such as is found in an estuary.

The researchers analyzed sulfur and oxygen isotopes — forms of these elements with the same number of protons, but different masses — in 51 fossilized tetrapod bones from locations in what’s now Greenland and China. Compared with freshwater, seawater has a higher ratio of the sulfur-34 isotope relative to sulfur-32. The tetrapod bones tended to show elevated sulfur-34, the researchers report, suggesting that the creatures spent at least some time in seawater. But oxygen isotope analyses of the bones show that freshwater was also present, arguing against a purely salty environment such as an ocean.

The results challenge a long-held view that the earliest tetrapods emerged from freshwaters, such as rivers or lakes. In 1929, the first Ichthyostega fossils were found in a series of red sandstone layers in eastern Greenland that geologists once thought had been deposited in a freshwater environment. But later discoveries of tetrapod fossils found associated with known marine species suggested that the early walkers may have lived in saltier waters than once thought.

An ability to tolerate different salinity environments could have helped tetrapods — a group that includes today’s amphibians, reptiles and mammals — survive a mass extinction of ocean-dwellers that occurred by the end of the Devonian Period about 359 million years ago, the researchers say.

Liebster Award, thank you Hayley!

Liebster Award

Hayley of the Zoologish blog has been so kind nominate Dear Kitty. Some blog for the Liebster Award. Thank you so much for this kind gesture, and best wishes for your zoological research and blogging!

The rules of the Liebster Award are:

1. Acknowledge the blog which nominated you.
2. Answer the 11 questions your nominator asked.
3. Nominate 11 other bloggers.
4. Ask them 11 questions.
5. Let them know you have nominated them.

Hayley’s questions, and my answers, are:

1. What was your first job? Processing flower bulbs.

2. What’s the best advice you’ve ever gotten? Get a computer.

3. Favourite season and why? All seasons have their good sides. At the moment I’d say spring, because it is spring now and there are swifts 🙂

4. Favourite TV show? David Attenborough’s BBC wildlife programs.

5. When did you first travel alone and where did you go? Texel island.

6. Why did you start a blog? See here.

7. What did you want to be when you were a kid? A paleontologist.

8. Would you rather travel into the future or the past? Probably the future; provided there will not be a nuclear war.

9. Do you have any siblings? Two sisters. One of them alive. The other one died at a young age.

10. Can you cook well? Not very well. But I am still alive 🙂

11. What is the next thing you plan to learn? About migrating birds of Rügen island in Germany. I traveled to that region over a year ago, but then a storm prevented the ship from sailing to Rügen.

My questions are the same as Hayley’s.

My nominees are:

1. Tale Spinning

2. The Recipe Hunter

3. Eva Newermann

4. Discovering Belgium

5. What you blog about

6. Consider Faith: A Blog on Christian Social Justice

7. 2 Cats and a Blog

8. Nature and more !

9. DMQuotes

10. Blind Injustice

11. hithame halawa pigeons

Thai hermit crab’s new home, a food tin

This video says about itself:

Crafty Hermit Crab Finds a New Home in a Food Tin | BBC Earth

1 June 2018

With shells disappearing because of tourists, hermit crabs in Thailand have turned to rubbish to solve their housing crisis.