Tag Archive: invertebrates


Umwelt

tick

A tick crawling along the ground. Image taken at Ano Nuevo nature reserve.

Imagine for a moment that you were a tick. What would your world be like? A tick’s world consists of only 3 sensory cues. Three. First, they can detect light. This helps them to climb up tall grass to get higher off the ground and in a spot they are more likely to find a passing meal.

tick

A tick now climbing up some blades of grass. Image taken at Ano Nuevo in California.

Once high up on a blade of grass, she waits for her second cue, the smell of butyric acid-a mammalian chemical by-product. When this smell comes by, she knows food is near and will drop off of her plant. An individual tick has been known to wait as long as 18 years for this precious cue.

Her last cue is warmth. Warmth indicates where blood is running close under the skin. Finding a warm spot, she burrows in, drinks the blood, drops off her host, lays her eggs and dies. She can’t taste the blood she’s been waiting so long for. In fact, she will drink any fluid that is the right temperature.

That’s it. Three things a tick can sense throughout its entire life. That’s its Umwelt, which is a term that means “the surrounding world” and is used to describe the unique and  limiting sensory world of every single animal species. Even within a species, individual animals can perceive the world differently.

A ticks Umwelt is incredibly simple. However because of this simplicity, her actions are unfailingly certain, with no distractions.

It’s wonderful to imagine what the world must be like to other animals. What do they experience that we don’t? What can we sense that they cannot? I plan to go into this in more detail in future posts. For the moment, consider our Umwelt and how very limiting it is. Even within our species, each of our brains is interpreting the world around us in a slightly different way. Sometimes before a stimulus even gets to our brains the hardware that captures it can be different between individuals. Take for instance our eyeballs. If we remove technology like glasses and lenses, think of how differently human beings would see the world. Even with those glasses and lenses there are differences.

We rely so much on our senses, it’s easy to imagine that the world holds only what we can experience. A great example of this is the discovery of color blindness. Although almost 10% of humans are color blind, color blindness wasn’t discovered until 1793, when a chemist named John Dalton, who had been working for years on colors of chemical compounds, realized that he himself was color blind. Imagine! It’s so easy to assume that everyone else senses what you do!

So next time you say the sky is blue and your friend says its purple, maybe they’re not being argumentative, maybe they’re telling the truth!

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What’s going on?

Dear Backyard Zoologist readers,

You’ve probably noticed a huge drop off in posts recently and I wanted to let you know what’s going on. In all honesty, I began this blog over a year ago because I enjoy sharing information and pictures of awesome wildlife. I still do, but at the moment I have a lot of cool but time consuming things going on and creating these posts on a regular schedule is starting to become more of a chore than something I do for fun. So, I’ve decided to only write new posts when the spirit moves me instead of on a regular schedule, to eliminate the dreaded deadline of Monday and Friday. Still, I hope you’ll check in periodically to see what’s new or better yet, sign up for e-mail notifications to let you know when I do post something new.

I still have lots to share…for example, did you know that this animal:

anemone

A giant green Anemone. Image taken at Fitzgerald Marine Reserve tidepools in California.

is used as a vertebrate heart stimulant? Or that this animal:

armadillo

A 9 banded armadillo. Image taken at the San Francisco Zoo.

always gives birth to identical quadruplets? And naturally grows the bacteria responsible for leprosy on its feet? Scientists couldn’t cultivate this bacteria in a lab, so they brought in live armadillos to collect the bacteria to work with.

Or that this animal:

tree shrew

A tree shrew. Image taken at the Oregon Zoo.

Is very smart and has a larger brain size to body mass than humans do?

Or that this animal:

kingsnake

California kingsnake, Kali, my personal companion.

Is called a kingsnake because it eats other snakes, including rattlesnakes and is immune to rattlesnake venom?

Or that these animals:

rock doves

Rock doves, a.k.a. pigeons. Image taken in San Francisco.

are one of the few birds that feed their young a type of milk?

Or that this animal:

marine toad

A marine toad. Image taken at the San Francisco Zoo.

is one of the only toads that will sometimes eat vegetation and dead things? While other frogs and toads want to eat only moving things, this toad is even attracted by dog and cat food left in yards.

Or that this animal:

lionfish

A lionfish. Image taken at the California Academy of Sciences.

is covered in highly venomous barbs and that dolphins will sometimes grab these fish by their tummies and use them as weapons to catch fish hiding in crevices?

Hypnotic Swirls

hornet's nest

A white faced hornet nest, complete with cute hornet face poking out. Image taken by Dawn Collins.

A colleague of mine sent me these beautiful pictures of a white-faced hornet (aka bald-faced hornet) nest. These wasps are a relative of yellow jackets and not true hornets.

hornet nest

A white faced hornet nest. Image taken by Dawn Collins.

And They All Go Marching Down

ants

Spiky ant. Image taken in Iquitos, Peru.

Two exciting stories of ants for you. The first is how some species of ants have designated food testers to make sure a food supply is not poisonous before the rest of the group gets it. You can read about that one here. The second is about a study suggesting that ants are capable of performing simple arithmetic calculations. Here is the actually publication, if you want the sciency version and here is the link to Discovery’s summery.

Don’t Look Down

wasp

An invasive species, this wasp thrives partially because of its ability to handle its competitors. Image by Nigel Jones.

This wasp has been observed in an interesting competitor-handling behavior. When it’s at a food station, enjoying its noms, and some ants come by to take part in the feast, these wasps will pick them up, fly them away and then drop them from the sky. Despite being quite a far fall, the ants usually survive, but with a lesson well learned. They will usually abandon the feeding station in search of safer, less painful foods. Before you take pity on the ant, it’s important to know that these ants will bite and spray acid on their competitors. You can see why the wasp doesn’t want them around. Read more about it here.

Some cute

Hi Backyard Zoologist readers,

Sorry about the missing posts last week, as I’ve been super busy with family visiting and work. I will be starting up back on schedule again on Friday. Until then, have some cute:

chubby chipmunk

A chubby chipmunk. Image taken at Lake Tahoe, California.

Vanessa

Vanessa, the most beautiful chicken that ever lived. Image taken at the San Francisco Zoo.

cuttlefish

This cuttlefish is like "Please love me. I'm cute." Image taken at the California Academy of Sciences.

flies

Copulating Flies. Image taken in Iquitos, Peru.

While this video has penguins mating, which is clumsy comedy, my favorite part is the little bit of penguin voyeurism. Watch the behavior of the penguins around the young couple.

Don’t have a Valentine? Don’t worry. This leopard tortoise can show you how it’s done. He just found himself a nice log…

Last, but not least, the delicate dance of mating cuttlefish:

On a side note, Backyard Zoologist is going to be updated two days a week now, on Mondays and Fridays. I will resume the three-days-per-week schedule in the fall.

Do NOT Taunt the Octopus

octopus

Do not taunt the octopus. Image stolen from Oddlyspecific.com.

Bioluminescence of the Sea

atolla

This jellyfish will light up when attacked and can be seen for 300 feet. Image by Steve Haddock of the Monterey Bay Aquarium Research Institute.

Find some more amazing biolumenescent creatures here.

Family Ties

paratrechina longicornis

Paratrechina longicornis. Image by April Nobile/Antweb.org.

How does this ant mate with its relatives and avoid the genetic consequences of inbreeding? Find out how here.