Reduction of gene flow. However, speciation might also happen in a population with no specific extrinsic barrier to gene flow. Imagine a situation in which a population extends over a broad geographic range, and mating throughout the population is not random.
The Internal Revenue Service places restrictions on how far back you can amend your tax return, regardless of whether you owed tax or received a refund. Filers must use Form 1040X to amend a return and should only file an amendment to report certain changes. You have three years from the due date of the original return or two years from when you paid tax owing to submit an amended return. A pen next to an income tax form.
How many years back can you get a tax refund? The IRS Statute of Limitations allows you three years from the filing deadline to file your prior year return and claim your refund. For example, the last day to claim your tax refund for the 2013 tax year is April 15, 2017. This is because the deadline date was April 15, 2014. Keep in mind that they also have the same amount of time to audit you and up to ten years to collect any unpaid tax.