Even Apple's (NASDAQ:AAPL) iPhone is mortal from time to time.

ABI Research data finds that the iPhone claimed a 16.6% slice of the global smartphone market during the holiday quarter, a sequential dip from the 18.1% it notched during the third quarter.

This sounds grim, at first. Apple's latest resurgence has been triggered by the wild popularity of its wireless devices. If the iPhone has peaked in popularity, it comes at a lousy time, with the iPad -- essentially a larger iPhone, though technically closer to an iPod touch on growth hormones -- set to hit the market next month.

In a Wall Street Journal blog entry, an analyst from the research firm compared the iPhone to Motorola's (NYSE:MOT) RAZR -- the flavor of the month a half-dozen years ago.

I don't buy it -- and not just because I upgraded my 2G iPhone in December.

"The last time the iPhone took a dip in market share was in the fourth quarter of 2008," notes the blog entry.

Wait a minute! Clear the shovels and open the casket. This isn't the iPhone dying. This is just a case of seasonality.

It makes perfect sense. Apple has updated its phones every summer, so naturally they're going to be hot sellers during the calendar year's third quarter. Early adopters jumped on the 3GS this past summer, just as the iPhone 3G served as their trampoline a summer earlier. Comparing iPhone market share sequentially doesn't make sense, especially with its rivals typically flooding the market just before the holidays.

Strategy Analytics -- another data tracker -- pegged Apple's slice of the smartphone market at a mere 10.8% last year. In other words, let's not bury the iPhone until we see year-over-year weakness.

Killing the iPhone prematurely would be stupid.

There is a glut of product out there. Research In Motion (NASDAQ:RIMM) is holding up well against Apple with its BlackBerry devices. Smaller players include Palm (NASDAQ:PALM) and the growing number of companies making smartphones based on Google's (NASDAQ:GOOG) Android platform.

This is a market that will intensify. Microsoft (NASDAQ:MSFT) Zune Phone chatter continues to grow. This is all healthy. It doesn't seem as if anyone is going to stop Apple from selling millions of smartphones every quarter -- and probably even more if and when we get the fourth version of the device this summer.