Archivos de Diario para agosto 2021

lunes, 02 de agosto de 2021

Species Spotlight: The Harlequin Ladybird

Hi everyone,

This week's species spotlight focusses on what is, now, a very common species in the UK - the harlequin ladybird (Harmonia axyridis).

This familiar and fascinating species can teach us something important about both wildlife recording and about species in general.

First let's get one thing straight - contrary to popular childhood rumours, the number of spots on a ladybird's back is nothing to do with how old they are! Different ladybirds have different markings because they are different species (most of the time... read on to find out more). In fact, there are approximately SIX THOUSAND species of ladybirds! Ladybirds are a family of beetles, known as the Coccinellidae family. So, onto one of these species, the harlequin...

A native of Asia, the harlequin ladybird only arrived in the UK in 2004, but quickly established itself as our most common ladybird species, taking the title from our native 7-spot ladybird (Coccinella septempunctata). The harlequin has been able to do this as it is a voracious predator with an aggressive attitude - not only will it outcompete other ladybird species for aphid prey, it will also eat the eggs and larvae of other species too! The same thing happened in North America in the late 1970s - the harlequin was introduced to control aphid populations, but quickly began outcompeting native species, and is now the continent's most common species.

This brings us on to an important point about wildlife recording, and why the pictures you all upload are so important. Citizen science is a vital tool in understanding which species are common and which are rare, and how this changes over time. These patterns help biologists work out how things like climate change, urbanisation, agricultural practices, and habitat loss affect species, and how species respond to them. This tells us something about the state of health of populations, ecosystems, and the planet in general.

Therefore, if you're thinking it's pointless taking a picture of a species you see all the time, that is NOT the case! If a species is common, it is good to make a recording of it, as this shows scientists that the species is indeed common, and this helps scientists track species declines/rises over time, as with our 7-spot and harlequin ladybirds. So don't worry if you're not finding any rare species in your recording - your pictures of common species are just as helpful!

Let's look more at the species itself now. If you look at the Wild Watch observations page, you will see, currently, we have five harlequin observations, and each looks different from the other! This is not an identification mistake; it's because the harlequin ladybird is EXTREMELY variable in how it looks, with about TWENTY different forms existing, all of this one species! They can be red and have anywhere between zero and twenty-two black spots; they can be black with red spots, or black with no spots; they can be orange (again, with or without spots); or even a complex pattern of red, orange, and black!

This shows us that relying on looks alone is not enough to tell species apart, even though this is usually the simplest and most reliable way. However, if we relied solely on looks, we would split the harlequin into about twenty species instead of one, and I think, with over 6,000, we have quite enough ladybird species already!

So how do we tell species apart if not by looks alone? Taxonomists (biologists specialising in classifying things) have several methods up their sleeves, the most common of which, nowadays, is to use DNA. Taxonomists can also look at mating behaviour and phylogeny (the evolutionary relationships between organisms), but the answer still isn't always clear. This is because, as ridiculous as it sounds, biologists still aren't exactly sure what a species is! As I will write about in a future blog post, the idea of a "species" is actually very messy (as most things in biology are), but that really will require another post to explain. I will choose some species that gives us the opposite problem of the harlequin ladybird (i.e. looks near-identical, but are actually separate species) to explain this more in the future.

Anyway, I hope this has given you the confidence to know that WHATEVER you upload to this page is really useful for present-day and future scientists alike! Keep up the awesome work everyone and I'll be back with another blog post soon.

Diolch
Kieran

Publicado el lunes, 02 de agosto de 2021 a las 10:58 AM por kieran-182 kieran-182 | 0 comentarios | Deja un comentario

lunes, 09 de agosto de 2021

FILM TIME!

Hi everyone,

Myself and my colleague Josh have been filming and editing some videos to help people learn a bit more about citizen science, wildlife spotting, and Wild Watch. These videos were originally recorded for the citizen science group in New Jersey who are making use of this project in their club, and I've made an edited version for you all to enjoy.
You can access the video here - https://www.youtube.com/watch?v=XgizZmqZbho

The video contains information about citizen science and why it's so beneficial, why wildlife-spotting projects are so important, and a little bit more about the technology behind iNaturalist.

I'll be back tomorrow with a new Species Spotlight.

Thank you and enjoy
Diolch a mwynhewch!

Kieran

Publicado el lunes, 09 de agosto de 2021 a las 04:25 PM por kieran-182 kieran-182 | 0 comentarios | Deja un comentario

miércoles, 11 de agosto de 2021

Species Spotlight: Slow Worm

A very exciting Species Spotlight this week as we look at a rarity for our project - a reptile! User rachall1 photographed a common slow worm (Anguis fragilis) last week, which is only the second reptile we've had all project.

The slow worm is NOT a worm (although, to be fair, it's not the quickest). It is actually a lizard! This is a great example of why we have scientific names for organisms (the latin bit in brackets above). The common names for species are often much older than the scientific (binomial) name - the binomial system was only formally introduced in the early 18th Century by Carl Linnaeus, well before much of our current taxonomic knowledge was founded. The binomial name, as well as avoiding confusion between a single species that have lots of common name (looking at you cougar/puma/mountain lion/catamount/panther/painter/ghost cat/red tiger/silver lion....), also tells us something about the taxonomy and evolution of the species. The Anguis genus is a group of legless lizards, and we can follow its family tree back to see its in the Anguidae family, which is a family of lizards.

So let's take a look at this lizard. It's found throughout the UK, although it's most common in Wales, as well as much of Central and Western Europe. Along with the sand and viviparous lizards, it is one of only three lizard species in the UK (and ten reptile species overall), and as such it is granted protected status, meaning it is illegal to harm or kill them (not that our domestic cats pay any attention to this law - they are their biggest cause of mortality).

Slow worms are semi-fossorial, meaning they spend much of their time hiding underneath things, such as compost piles and leaf litter. They are able to shed their tail in order to flee from danger, which is one of the tell-tail (sorry) signs that they're not a snake. Let's take a closer look at this snake/lizard confusion...

Snakes and lizards are part of the same order of reptiles (Squamata/the squamates), but they belong to different groups within this order. The exact details are a little bit complex for this blog post (I've said it before and I'll say it again and again and again: nothing is ever straightforward in biology!), but a relatable (another terrible pun) example is this:
Imagine you are a lizard. Everyone in your family that shares the same Nain/Grandma as you is also a lizard. Your distant cousins are all snakes, and they have a different Nain. However, you all have the same Naina/Great Grandma, so you're all squamates!

Anyway, I promise this is going somewhere - I know you're all here to find out "Where are their legs?!"
Well, looking again at the family tree, the ancestors of these lizards (the slow worm group) lost their legs at some point during their evolution, but their even more ancient ancestors did have legs at some point. Looking at the evolutionary history of animals is much better way of categorising them compared to their morphology. A slow worm may look like a snake due it is legless nature, but the family history tells us otherwise. Other features that distinguish these lizards from snakes are their aforementioned ability to shed their tail, and the fact that they blink with their eyelids (snakes don't have eyelids - they just have a clear scale covering their eyes).

Losing things and/or discovering new things is a very common trait of evolutionary families, and the precise reasons why are as various as the examples themselves (although it always boils down to the fact that, at some point in time, a particularly characteristic was no longer necessary/now very necessary). The ancestors of penguins could fly, but penguins lost the ability; snakes and legless lizards lost the legs that the rest of the squamates have; birds lost their teeth.

So now we know a bit more about telling slow worms and snakes apart... but telling slow worms apart is a different story! They are something called a species complex, where several distinct species look very, very similar, to the point where their morphology can't really help. This is basically the opposite problem to the one posed last week by the Harlequin Ladybird! However, I think we've probably had enough taxonomy for one week, but I'll return to species complexes in the future when I put a butterfly under the Species Spotlight! For now, check out local woodland edges, grasslands or meadows to find slow worms near you (just don't bring your cat).

Diolch and hwyl fawr
Kieran

Publicado el miércoles, 11 de agosto de 2021 a las 03:36 PM por kieran-182 kieran-182 | 0 comentarios | Deja un comentario

miércoles, 25 de agosto de 2021

Species Spotlight: Common Box Turtle

Hi everyone!

Apologies for the lack of Species Spotlight last week. Xplore hosted our first self-run Darganfod Science Festival last weekend, so last week was very hectic! To make up for it, we'll do two Species Spotlights this week, beginning with the common box turtle (Terrapene carolina), spotted by participant looghna_dainty_mac_bay in Hendersonville, Tennessee.

First off - what an awesome observation! I'm sure those of us in Wales/elsewhere in the UK are mind-blown by the thought of spotting a wild turtle* just knocking about on our doorsteps. However, I'm sure this is, if not a common, a relatively unsurprising occurrence in Hendersonville, given than the common box turtle is the state reptile of Tennessee (If we had a national reptile in Wales, we'd have about three to choose from).

  • or tortoise - read on to find out the difference between a turtle and a tortoise. Until then, I will use the term "turtle" to mean both turtles and tortoises (this is for a good reason, as you shall see).

The common box turtle gets its name from the fact that, as well as being able to retract its head into its shell like the rest of the turtle order, it can actually completely enclose itself in its shell, forming a box! It is able to do this as it possesses a hinged lower shell.

Contrary to cartoon depictions (they have a lot to answer for), a turtle's shell is not some sort of mobile home, analogous to that of a hermit crab's. No, a turtle's shell IS the turtle! The shell is formed from the turtle's own bones, including its ribs, parts of its pelvis, and parts of its spine (this is the case for all turtles, not just the common box). The cool/mildly horrifying thing is that a turtle hiding in its shell is basically the equivalent of us hiding in our own ribcages. For an idea of what this might look like (because I'm sure that's where your mind just went) check out this webpage - https://www.demilked.com/animal-anatomy-compared-to-human-satoshi-kawasaki/ - this shows the human equivalents of several animal anatomies, including the fact that a horse's "foot" is basically the same as us walking around on our fingers.

On the subject of turtle shells - please do NOT ever paint on a turtle's shell. As we have just seen, their shell is a living part of their body. They absorb vitamins through their shell via UV radiation from the Sun, so waiting their shell can make them very poorly, or may even be fatal.

The common box turtle has several subspecies (I know we've been talking about species and their confusions and I now I've just thrown another word into the mix - I can only apologise on behalf of biologists everywhere). A SUBSPECIES is a rank below species. I said a few weeks ago that biologists still aren't settled on what a specie is, but one of the most common traits that a group of animals must possess in order to be classified as a species is the ability to interbreed with one another to produce FERTILE offspring. That word "fertile" is important - lions and tigers, for example, can mate to produce ligers or tigons (yes, really), but these are all sterile.

Subspecies can interbreed to produce fertile offspring, so they are part of the same species. Subspecies are distinguished purely on morphology (i.e. what they look like). This is one of the rare times when morphology is the only thing needed to make a distinction. The common box turtle has six subspecies, generally distinguished by their shell patterns.

(A side note on subspecies - the most well-known subspecies is.... the dog! As in domesticated/pet dogs! They are all part of the wolf species (Canis lupus), so, yes, you are literally sharing your house with a wolf. Canis lupus is actually the species with the most subspecies: 38 in all! They're all wolves, but are distinguished by their looks. Other wolf subspecies include the arctic wolf and the dingo).

Anyway, let's move on to the big question - what's the difference between a turtle and a tortoise? Are turtles tortoises? Are tortoises turtles? WHAT'S A TERRAPIN? Do they even exist (I'll answer that straight away: yes, they're not fish.... there's no such thing as a fish... if someone finds a fish, I'll do a blog post about that).

Turtle is the name of an Order of reptiles. Reptiles are a Class, which is a higher rank than Order, and includes lizards, snakes, and crocodilians, as well as turtles/tortoises. Example equivalents: insect is the class, beetle is the order; mammal is the class, primate is the order). There are over 350 species in this order - that's a lot of turtles!

The turtle order (which sounds like a great Teenage Mutant Ninja Turtles spin-off) has the scientific name Testudines, but it is most often referred to simply as turtles. This order contains ALL the animals that we refer to as turtles, tortoises, or terrapins: "turtle" is basically the catch-all term for anything that looks turtle-y.

Tortoises and terrapins refer to just a few specific animals in this order. That means that all tortoises and terrapins are turtles, but not all turtles are tortoises (or terrapins). Specifically, "tortoise" is a family in the turtle order, with the scientific name Testudinidae (I know, I know, it sounds so similar to Testudines). Tortoises differ from the rest of the order in several ways, including being entirely land-dwelling, whereas other turtles spend at least part of their life cycle in water; and having "elephantine" limbs, rather than flipper-like limbs.

Terrapins aren't really a proper scientific "thing" (basically they're not all a distinct group, like tortoises). Instead, terrapin is just a name given to several species of small turtle. Terrapins can be found all across the turtle order, whereas tortoises are ALL in one group (family).

Wow! I know that's a lot of info, so let's sum up - turtles are a group of reptiles; tortoises are a group of turtles; terrapins are a general name for some small turtles.

We'll finish with some tortoise news! We tend to think of tortoises as docile, plodding, unthreatening beings (because, for the most part, they are). However, recent footage from the Seychelles has shown a tortoise stalking and eating a live bird! This is completely unprecedented behaviour, and tortoises are hardly built to be hunters! This goes to show how much about the natural world we still have to learn - so keep sending your observations in! Read all about it and even see the footage here - https://www.smithsonianmag.com/smart-news/giant-tortoise-stuns-scientists-eating-bird-180978511/

I'll be back later in the week with a new Species Spotlight.
Diolch
Kieran

Publicado el miércoles, 25 de agosto de 2021 a las 10:30 AM por kieran-182 kieran-182 | 0 comentarios | Deja un comentario

viernes, 27 de agosto de 2021

Species Spotlight: Great Pied Hoverfly

Time for the second part of our Species Spotlight double header this week! Today we are looking at rachall1's great pied hoverfly, also known as the pellucid fly, (Volucella pellucens) observation.

I want to talk about this species because it is part of a family of insects that is not championed as much as it should be...

V.pellucens is part of the hoverfly insect family (Syrphidae). This is a family in the fly order (Diptera), which includes the common house fly. This order has only one pair of wings, unlike the rest of the winged insects, which have two pairs. There are over 270 hoverfly species in the UK and about 6,000 species globally. Most have wonderful, unique patterns, making them popular among insect-spotters. V.pellucens has a gorgeous large cream band around the middle of its abdomen, which, in certain lights, is translucent, allowing you to see through the insect! (Hence the name "pellucens", from the word "pellucid")

Hoverflies are often mistaken for bees or wasps because most hoverflies have yellow and black colouring, similar to their hymenopteran counterparts. However, you can easily spot a hoverfly on the wing (i.e. whilst it's flying) because of their unique flying style - often they can be seen hovering around flowers (hence the name), and when they're flying about they tend to zip quickly from place to place, hovering in between, in contrast to bees and wasps, which tend to be a bit more amble-y* and less straight-line-y when flying*.

  • surprisingly, these aren't proper entomological terms

What you'll notice in rachall1's picture is that V.pellucens has a really large, striking pair of eyes. These eyes likely look familiar, as they are characteristic of the Diptera order. This is another easy way to tell hoverflies apart from bees and wasps - flies' eyes are positioned on the top of the head, forward facing, whereas bees and wasps have eyes on the side of their head.

So now you know how to spot the difference between those yellow and black things buzzing around your garden. But why do hoverflies look like bees and wasps in the first place? It's all to do with protecting themselves....

In biology, we use the term "mimicry" to describe situations where different organisms resemble each other. These resemblances don't have to be visual - they can also be acoustic or chemical or tactile. There are several reasons why they may have evolved to do this (because it is almost always an evolved trait, rather than chance), but they generally fall into three main camps: defensive (pretending you're dangerous), aggressive (pretending you're not dangerous), or reproductive (pretending you're... well you can fill this in yourself).

Hoverflies' mimicry falls into the first camp - hoverflies are NOT harmful at all, but they mimic bees and wasps, which can be dangerous to other animals due to their sting. They do this to avoid predation - by looking like potentially dangerous bees/wasps, they are trying to fool would-be predators into avoiding them. When the mimic organism looks like the thing it's copying, but does NOT share its dangerous/unpalatable attributes, it is known as BATESIAN MIMICRY, after Henry Walter Bates who hypothesised the anti-predator adaptation of some mimics. Another way of thinking of Batesian mimicry is a "sheep in wolf's clothing".

Mimicry is a huge and really, really fascinating topic in biology, which I will try to return to in a future blog post, but for now let's look at why hoverflies are really important insects for humans....

Hoverflies are very important pollinators, second only to bees! Hoverfly pollination is nowhere near as well-studied by scientists or as well-known by the public, but it is absolutely crucial for our ecosystems. I think all the wonderful "SAVE THE BEES" messaging really should say "SAVE THE BEES AND HOVERFLIES". Furthermore, whilst adult hoverflies tend to feed on nectar and pollen, the larvae of many species are voracious insectivores (they love eating insects), with aphids and other crop pests being among their favourite prey. As such, they are brilliant biological controls, keeping pest populations in check, meaning they are very important to farmers around the world, saving food and money. Hoverflies are brilliant!

Let's finish by talking a little more about V.pellucens. This is a widespread species, being found across the UK, the rest of Europe and parts of Asia, and is typically found in hedgerows and woodlands. Adults are generalist pollinators, meaning they are not fussy about which flowers they visit. One of the coolest things about V.pellucens is that its larvae live in the underground nests of the common wasp (Vespula vulgaris). Adult female V.pellucens enters the nest to lay her eggs. Once they hatch, the larvae feed on the wasp larvae and any dead adults.

So there we have it - hoverflies are gorgeous, harmless (if you're not wasp larvae, which I don't think any of your are), and very very important! If you're interested in finding out more about these brilliantly-patterned creatures, there are some great Facebook groups, such as UK Hoverflies.

Enjoy the sun over the bank holiday weekend - a perfect chance to do some spotting!

Kieran

Publicado el viernes, 27 de agosto de 2021 a las 10:43 AM por kieran-182 kieran-182 | 0 comentarios | Deja un comentario

martes, 31 de agosto de 2021

Science Spotlight: Climate Change

Hi everyone,

Before this week's Species Spotlight, I thought I'd do a slightly different post about one of the scientific aspects of this project.

This morning I was on Calon FM talking about Wild Watch and sharing a platform with one of Wild Watch's most prolific recorders, my friend Rachel (rachall1) from Climate Cymru. Climate Cymru are a political action group that are encouraging the Welsh Government to place the climate emergency at the top of their priorities list, and to ensure the concerns of the Welsh public are heard.

On the Calon FM show this morning we discussed how we can help combat climate change, particularly the little things that we can all do. So I thought I'd do a blog post about how Wild Watch can help. I hope this is both informative from a scientific perspective, but also empowering and uplifting - I know that the climate and nature crises can seem utterly overwhelming at times, but it is the very scale of these problems that mean there are plenty of opportunities for us to help.

Wild Watch is, of course, a wildlife data collection citizen science project; indeed that is what iNaturalist itself is. You can watch a short video about citizen science, iNaturalist, and the importance of wildlife data collection here: https://www.youtube.com/watch?v=XgizZmqZbho
It is worth re-emphasising that all the pictures you have been uploading are part of a huge citizen science project and that by doing that YOU are taking part in real scientific research!
Let's look in more detail about how these sorts of projects (including Wild Watch) can help combat the climate and nature crises...

Firstly, the greatest strength of these sorts of citizen science projects, from a scientific perspective, is the sheer volume of data we collect (thanks to you guys!). This arms scientists with loads of information to help them make discoveries and analyse what is going on in our ecosystems - the more data the better!

By finding out what species are present in an area, scientists can learn something about how climate change is affecting different species or different areas. For example, it may be that a species' geographic range has now expanded because an area that was once too cold for it to survive is now warm enough. Or it could be that a species is lost from an area due to the climate changing, as the species evolved to live in a particular set of conditions that have now disappeared. In this way the species act as indicators, telling scientists how much the climate is changing in a particular area and what effect this is having on the ecosystem. It's like a doctor diagnosing a patient - by looking out for tell tale symptoms (tell tale species), they can work out what exactly is wrong (how much the climate is changing).

Knowing this helps scientists and environmental organisations make their cases to governments and policymakers. They can show them how bad the issue is, encouraging them to take swift and decisive action, or they can reveal specific problems in an area and come up with suitable solutions.

Species data also helps protect natural areas, or encourage a targeted increase in biodiversity through managed means (such as creating green spaces), as scientists can use the presence of species to advocate for an area to be protected (e.g. to stop a field being built on). This is crucial to fighting the climate and nature crises. The latter is fairly obvious: nature needs a home! But the former is just as important, if a little less obvious - nature is one of our best tools in regulating the climate....

We are all familiar with the carbon trapping abilities of plants, but it's so much more than that. Our ecosystems are complex, dynamic things that have evolved over millions of years to work in harmony with the world around them. By protecting these natural networks, we are helping maintain a balance in so many natural systems, including some we likely don't know about, such as water cycles, nutrient cycles, and air filtering. Furthermore, more diverse ecosystems tend to be better at this, as well as being more resilient to change. So by protecting and promoting biodiversity, we are helping create a healthier planet for all life on Earth.

Promoting biodiversity doesn't have to be done on a grand scale - we can all do our bit in our little patches! Here is a Climate Cymru article from Rachel about how you can promote biodiversity at home by rewinding your garden! https://climate.cymru/rewilding-tackling-the-climate-and-nature-crisis-from-home/

Finally, wildlife spotting helps raise public awareness of nature, particularly local nature (as most spotting is done on your doorstep). Increased awareness is known to lead to an increase in concern and care. I'm sure you can see this from you're own spotting - when you know just how many species are living in your area, you feel a surge of affection towards the area and are more likely to want to take action to protect it. Fostering a sense of belonging with and caring towards nature is absolutely vital if we are to work for real sustainable change - it is only through our collective actions that we can have a truly sustainable society, in which we can appreciate our place as part of the global ecosystem. After all, we share this planet with all the wildlife we spot!

So keep your pictures coming in and enjoy the sights, smells, and sounds of whatever natural areas you have on your doorstep, big or small!

Diolch yn fawr
Kieran

Publicado el martes, 31 de agosto de 2021 a las 03:42 PM por kieran-182 kieran-182 | 0 comentarios | Deja un comentario