environment--->changes within a species?? (1 Viewer)

[ktl_edwards]

Can anyone help answer this question??

Describe how environmental changes have led to changes within an australian species.

Please can anyone help me out?

Thankyou heaps!:wave:

 

[ktl_edwards]

Can anyone please help me out here!!!


Please please please!!

 

[possessionless]

does the syllabus actually say australian species??

 

[ktl_edwards]

i'm not sure...it's just one of my assessment questions.

I can't find any websites and stuff....

any ideas??

 

[samthebear]

which dot point is it from? i know its from blue print of life but i mean the dot point and sub dot point which specifies what you need to do.

 

[ktl_edwards]

this is the blue print of life syllabus dot point

.analyse information from secondary sources to prepare a case study to show how an environmental change can lead to changes in a species.

But specifically for my assessment question it says i have to find an australian species.

I'm guessing i have to talk about the changes in the species due to
.changes in the physical environment
.changes in the chemical environment
.competition for resources

So can anybody please help me out here?

Or lead me to some ideas?

Thankyou!

 

[missanonymous7]

This is taken directly from my old 'Dot Point HSC Biology' book, ie not my own words, but I think it might help

Physical:
Physical conditions in Australia have changed over the past 25 million years, with increasing temperatures and decreasing rainfall. This has led to a change in plant vegetation from rainforest, to open woodland, to grassland. The changed vegetation has led to a change in the features of animals - the molar teeth of ancient kangaroos have become specialised with high crests for grinding to cope with the tougher vegetation. Kangaroo feet have changed for increased speed in grasslands.

Chemical:
As inland areas in Australia became more arid, a corresponding problem of high salt in the soil occured. This change in the chemical composition of the soil led to the evolution of salt-tolerant plants, such as the saltbush (atriplex).
(This next bit, I'm not sure if it's specifically Australian, but I wrote it down anyway: ) When DDT was first used to kill mosquitoes, low concentrations were extremely effective. In subsequent sprayings, much stronger doses were needed to be effective. The few mosquitoes which survived the first spraying had a natural resistance to DDT and this was passed onto their offsping. The population changed to become resistant due to selection by the DDT in the environment.

Competition for resources:
Over the last 200 years, many species have been introduced into Australia, such as sheep, rabbits, foxes, goats, pigs, prickly pear, wheat, Patterson's curse. This introduction has led to serious competition with native species for available resources. The competition has led to extinction of some species, others are endangered and the distribution areas have changed for many species, eg the burrowing bettong was once found in most arid and semi-arid regions but is now extinct on the mainland and restricted to four islands off the coast of Western Australia.

Source: Humphreys, K. Dot Point HSC Biology. Published in NSW Australia in 2008 by Science Press

Hope it helps. I suggest you try expanding on these

 

[ktl_edwards]

Thanks for that! i'm still a little confused though as it only asks for 1 australian species.

Like how can you talk about the kangaroo in regards to changes in chemical conditions in the environment and competition for resources? That's what i find hard to figure out.

But let me know if you have any suggestions?

Thanks once again!

 

[missanonymous7]

Wow, they like to make it difficult, don't they?

I'm really not sure of any examples that could be used for all three, sorry. I just tried flicking through the chapter in my uni biology textbook (which is absolutely massive ) on Australia's changing environment, but I couldn't really find anything that would be able to answer your question - it has different examples for each 'heading' or change in Australia's environment too.

I would suggest, as just a rough guide, looking at animals/plants adapted to 'desert' or arid conditions, as I'm thinking they would be more likely to have had to evolve to cope with physical and chemical changes as well as competition (by introduced species).

From my textbook, some extra things to consider that may or may not be helpful:

Physical changes in Australian environment - lots of land clearing and 'habitat fragmentation' has occured since European settlement.

Chemical changes - increasing soil acidification and salinity; atmospheric pollution.

Sorry I can't really help any more (maybe someone else can?)...good luck with it!

 

[ktl_edwards]

hey, thanks again for replying. I really appreciate your input!

So i guess i'm on my own for this question. It's not fair when they make these questions sooo difficult.

Hmmm not sure but do you know of any other changes in the kangaroo that has taken place due to the changing environment other than their teeth. That would help me out alot!

Any ideas?

Thanks

 

[missanonymous7]

Unfortunately I'm not really an expert on Australian wildlife (well not yet anyway. Maybe when I finish my degree though, hehe.) I can actually think of quite a few other adaptations the kangaroo has for Australia's climate, but they'd all be related to the 'physical changes' bit, not the other two.

I also have a kind of epic amount of uni work right at the moment, which is really annoying So I'm sorry I can't really help out much more right now, I kind of don't have the time. But yeah, just try looking at desert species, especially mammals etc. And maybe plants, even though they're pretty boring.

Sorry I can't really help much more! If I think of something I'll post it though. Just tell your teacher that he/she made it too hard

 

[Freddie09]

Hi, i'm kinda stuck on exactly the same question. thanks for the info on kangaroos though i think that might help.
Does anyone know how long the case study should be? they've only given just under a page for the answer do you think i need to fit it in here?
Thanks

 

[ktl_edwards]

"I can actually think of quite a few other adaptations the kangaroo has for Australia's climate, but they'd all be related to the 'physical changes' bit, not the other two."

Thats ok, i dont mind. I just need a few other things to talk about uno?

Good luck with your uni stuff,


Kimi

 

[Freddie09]

just found out some more stuff on Red's, just search the animal your doing as your case and heaps of stuff comes up on adaptation to the physical environment.

 

[missanonymous7]

just found out some more stuff on Red's, just search the animal your doing as your case and heaps of stuff comes up on adaptation to the physical environment.

This is true. Plus, just quietly...Wikipedia can be incredibly helpful for things like this... At least as a starting point, if nothing else.

 

[ktl_edwards]

hey guys,

thanks for all that information however i managed to finish the question! And i think i did pretty well! yay!

Thanks again,

Kimi

 

[sweet_groovi]

i just completed an assessment task that required me to write about a particular species' physical & chemical adaptations and in turn, how this had impacted upon the availability of resources.
if you were to look into the kangaroo for example, it was classed as a megafauna previously and now, have adapted to suit the australian climate. over time, australia has become drier, causing land to alter from a rainforest-like area to grasslands and woodlands, this altered the kangaroos diet, so in turn, their size decreased, along with the shape and size of their teeth. due to the alteration in diet and relative size, the kangaroo now has a longer tail and strong hind limbs to enable it to escape predators quickly.

hope that makes things a little easier.
i'm sure you'll be able to work out a few other things from the above lead..
meaghan.

 

[christoffpow]

Kangaroos

Physical conditions:
Lets say.. climate. Increased climate over the past 200 million years has seen increases in vast, dry areas = this has led to the bipedal hopping of kangaroos to cover more ground efficiently and with minimal energy. Teeth for grinding grass has also evolved in kangaroos, due to grass being the dominant vegetation - because of increased temperature/climate.

Chemical conditions:
Not sure here.. you could say something like, the increased oxygen levels has allowed for aerobic respiration of kangaroos and therefore contributing to their survival. Increased oxygen has also contributed to the formation of the ozone layer.. which reduces intensities of light hitting the surface allowing for kangaroos to grow in its current form

Competition for resources:
Introduction of dingoes to Australia has increased competition for food for the kangaroo and many other wildlife (tasmanian tigers), which could possibly lead to the kangaroo's endangerment.

Not necessarily dingoes as they don't eat anywhere near kangaroo's food.. but you get the picture.

No offense to your school but that assignment is ridiculous. It's virtually impossible to find a species, let alone one of Australian origin, to have evolutionised because of all 3 of the impacts of evolution. Usually its just one impact that causes evolution of a species.. After all evolution is a process that occurs characteristic by characteristic.. i believe.

 

[Kwayera]

Competition for resources:
Introduction of dingoes to Australia has increased competition for food for the kangaroo and many other wildlife (tasmanian tigers), which could possibly lead to the kangaroo's endangerment.

Not necessarily dingoes as they don't eat anywhere near kangaroo's food.. but you get the picture.

Incorrect. Dingoes are actually the main predator of kangaroos, and an important trophic regulator. Where there are no or few dingoes (aka behind the dingo fence), the population of kangaroos explodes, such that they become an agricultural pest. A better example here is how the introduction of the dingo ~4,000 years ago influenced the Australian ecosystem and its predator-prey relationships (given that the dingo is really Australia's only large land predator).

And don't ever refer to the thylacine as a "Tasmanian tiger". Biologists will laugh at you.