For this question lets take a trip to Slyo Dacas:
Slyo Dacas (sil-yo-dak-iss) is a world roughly the same size of Earth with a decent magnetic field and no moons.
The world is a bit drier than earth, its seas are shallower and smaller and its land more bit more arid on average.
The planet has plate tectonics, a day of 24 hours, and a year of 365 days.
The main difference though is its orbit: highly eccentric.
There are no seasons due to almost no axial tilt. However, since the orbit changes the climate so drastically for simplicity sake I will say it has seasons. Summer with the planet's orbit at closest approach to its star, and winter at it farthest reach.
Winter features the coolest temperatures where the poles are below freezing and the seas are at their greatest size and coolest temperatures. The planet looks a lot like the above picture.
Summer temperatures rise drastically. Most of the water evaporates into the atmosphere and massive cyclones rage across the planet drenching everything in hot rain.
A lot like this.
Now we know that erosive agents here on Earth help shape just about everything from mountains, coastlines, rivers, even individual rocks.
This planet has most of those processes as well, but in a more advanced pace and on a yearly schedule. The planet is also a bit drier. So taking these details into account my question is:
What can we expect from this terrain acted upon by rapid changes in climate?
Example: Would there be more sandy deserts, smoother canyons? No ocean cliffs? Please provide explanations.
How could plant and animal life adapt to survive the changes during the year?
Where would be the most likely/unlikely places to find that life?